Column averaging/row averaging circuit for image sensor resolution adjustment in high intensity light environment

ABSTRACT

A photo-sensor image resolution adjustment apparatus is in communication with an array of image photo-sensors that are organized in columns and rows and have multiple sensor types arranged in a pattern such as a Bayer pattern to detect light. The photo-sensor image resolution adjustment apparatus has a photo-sensor array decimation circuit to partition the array of image photo-sensors into a plurality of sub-groups. A column averaging circuit averages the light conversion electrical signals from common color photo-sensors within the sub-groups. A row averaging circuit averages the common color adjacent light conversion electrical signals from color adjacent rows within the sub-groups in high light intensity condition. In low light conditions, a row binning circuit integrates the common color adjacent light conversion electrical signals from color adjacent rows within the sub-groups.

BACKGROUND OF THE INVENTION RELATED PATENT APPLICATIONS

“An Image Sensor Having Resolution Adjustment Employing an Analog ColumnAveraging/Row Averaging for High Intensity Light or Row Binning for LowIntensity Light,” Ser. No. ______, Filing Date ______, assigned to thesame assignee as this invention.

“A Column Averaging/Row Binning Circuit for Image Sensor ResolutionAdjustment in Lower Intensity Light Environment,” Ser. No. ______,Filing Date ______, assigned to the same assignee as this invention.

1. Field of the Invention

This invention relates generally to image sensor array processing. Moreparticularly, this invention relates to circuits and methods foradjusting resolution of image sensors. Even more particularly, thisinvention relates to circuits and methods for adjusting resolution ofimage sensors by decimating the addressing of the image sensors intosub-groups of the array of the image sensor, averaging the columns ofeach of the sub-groups of the image sensor, and selectively averaging ina high intensity light environment or binning in a low intensity lightenvironment of multiple rows of the average of the columns of thesub-group of the array of the image sensors.

2. Description of Related Art

Digital Cameras employing CMOS image sensor technology include imageprocessing and JPEG (Joint Photographic Experts Group) compression foradjusting the resolution of the camera. In general, the image sensoroperates in several modes. It takes full resolution image in a relativelower speed (1 to 15 frames per second depending on the image format)which is stored in a memory. The image sensor must also acquire lowresolution images at high speed (about 30 frames per second) forviewfinder or short video. In most of the CMOS image sensor designs, lowresolution high speed images are acquired by decimation or partitioningthe image array in to groups of pixels and choosing a sub-set of thegroup of pixels to sub-sample a sub-set of pixels within the group ofpixels that has been selected to represent the whole image.

FIGS. 1 a and 1 b illustrate the sub-sampling of an array of Bayerpattern configured Complementary Metal Oxide Semiconductor (CMOS) ActivePixel Sensors (APS). The Bayer pattern, as shown in U.S. Pat. No.3,971,065 (Bayer), describes a format for a color filter array. In thearray as shown, the Bayer pattern has four sensors arranged in a two bytwo matrix of CMOS APS's. The CMOS APS's receive the Red, Green and Blueof the standard color video construction. One Pixel receives the Red,one the Blue, and the remaining two pixels receive the Green and aredesignated red (R), green-1 (G1), green-2 (G2), and blue (B).

In FIG. 1 the array is structured to illustrate a 3:1 ratio sub-samplingon the Bayer pattern. The array 5 of CMOS APS's shows a 6×6 array of theBayer pattern sensors. The array 5 is physically an array having 12pixels in the horizontal dimension and 12 pixels in the verticaldimension. The Bayer pattern groups these pixels into the 2×2 groups(Red, Green-1, Green-2, and Blue) of pixels. The sub-sampling thenfurther groups the pixels according to the ratio of the sub-sampling.Thus, each sub-group 7 a, 7 b, 7 c, and 7 d has a 6×6 array of CMOSAPS's that is further divided into a 3×3 Bayer pattern. In asub-sampling, a central Bayer grouping of each sub-group 7 a, 7 b, 7 c,and 7 d is chosen as the output pixels R^(O), G1^(O), G2^(O), and B^(O)of the array.

In general, the output pixels as a function of original image pixel (notconsidering the fixed spatial offset) information are given by:R ^(O)(k,l)=[R(2×n×k,2×n×l)]G1^(O)(k,l)=[G1(2×n×k+1,2×n×l)]G2^(O)(k,l)=[G2(2×n×k,2×n×l+1)]B ^(O)(k,l)=[B(2×n×k+1,2×n×l+1)]  (1)

where:

-   -   n is the decimation ratio of the sub-sampling of the array.    -   k is the counting variable for a row dimension of the sub        sampled array 15.    -   l is the counting variable for the column dimension of the sub        sampled array 15.    -   R^(O) is the red pixel of the sub sampled array 15.    -   G1^(O) is the first green pixel of the sub sampled array 15.    -   G2^(O) is the second green pixel of the sub sampled array 15.    -   B^(O) is the blue pixel of the sub sampled array 15.

Pixel sub-sampling reduces the output bandwidth that the frame rate canbe increased with same pixel readout speed. However, the drawback ofpixel sub-sampling is the lost of spatial resolution that will introducealiasing to the image. In additional, the image obtained from pixelsub-sampling has a very poor quality at low light level because of theeffective small sensing area.

The images sensors are increasing in size to accommodate the imageformats such as the Super Extended Graphics Array (SXGA) displayspecification that is capable of displaying 1280×1024 resolution, orapproximately 1.3 million pixels or the Quantum Extended Graphics Array(QXGA) display specification that is capable of supporting 2048×1536resolution, or approximately 3.2 million pixels. As the image sensorsbecome larger, and decimation ratio becomes higher, more and more imageinformation will be lost due to pixel sub-sampling.

To enhance the spatial resolution of decimated image, pixel binningand/or averaging is desired. Thus, the output pixels R^(O), G1^(O),G2^(O), and B^(O) of the array 15 will represent all the information ofits neighboring pixels of the sub-group 7 a, 7 b, 7 c, and 7 d of theoriginal array 5 of CMOS APS's. In general, for the n×n pixel binning,the value of output pixels R^(O), G1^(O), G2^(O), and B^(O) are:$\begin{matrix}{{{R^{O}\left( {k,l} \right)} = {\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {R\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}{{G\quad 1^{O}\left( {k,l} \right)} = {\sum\limits_{i = 1}^{n - 1}{\sum\limits_{i = 0}^{n - 1}\left\lbrack {G\quad 1\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}{{G\quad 2^{O}\left( {k,l} \right)} = {\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {G\quad 2\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}{{B^{O}\left( {k,l} \right)} = {\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {B\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}} & (2)\end{matrix}$

where:

-   -   n is the decimation ratio of the sub-sampling of the array.    -   i is the counting variable for the neighboring pixels in a row        dimension of the sub sampled array 15.    -   j is the counting variable for the neighboring pixels for a        column dimension of the sub sampled array 15.    -   k is the counting variable for a row dimension of the sub        sampled array 15.    -   l is the counting variable for the column dimension of the sub        sampled array 15.    -   R^(O) is the red pixel of the sub sampled array 15.    -   G1^(O) is the first green pixel of the sub sampled array 15.    -   G2^(O) is the second green pixel of the sub sampled array 15.    -   B^(O) is the blue pixel of the sub sampled array 15.

Similarly, for n×n pixel averaging, the value of output pixels R^(O),G1^(O), G2^(O), and B^(O) are: $\begin{matrix}{{{R^{O}\left( {k,l} \right)} = {\frac{1}{n \times n}{\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {R\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}}{{G\quad 1^{O}\left( {k,l} \right)} = {\frac{1}{n \times n}{\sum\limits_{i = 1}^{n - 1}{\sum\limits_{i = 0}^{n - 1}\left\lbrack {G\quad 1\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}}{{G\quad 2^{O}\left( {k,l} \right)} = {\frac{1}{n \times n}{\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {G\quad 2\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}}{{B^{O}\left( {k,l} \right)} = {\frac{1}{n \times n}{\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {B\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}}} & (3)\end{matrix}$

where:

-   -   n is the decimation ratio of the sub-sampling of the array.    -   i is the counting variable for the neighboring pixels in a row        dimension of the sub sampled array 15.    -   j is the counting variable for the neighboring pixels for a        column dimension of the sub sampled array 15.    -   k is the counting variable for a row dimension of the sub        sampled array 15.    -   l is the counting variable for the column dimension of the sub        sampled array 15.    -   R^(O) is the red pixel of the sub sampled array 15.    -   G1^(O) is the first green pixel of the sub sampled array 15.    -   G2^(O) is the second green pixel of the sub sampled array 15.    -   B^(O) is the blue pixel of the sub sampled array 15.

Equations (1), (2), and (3) indicate that the pixel sub-sampling has thelowest spatial resolution and no signal level enhancement. Pixel binninghas the high spatial resolution with highest signal level enhancement(factor of n²). Pixel averaging has the high spatial resolution, butwithout the signal level enhancement.

Each of the different image decimation techniques of CMOS APS's (imagesub-sampling, image binning, and image averaging) have their own set ofadvantages and disadvantages.

In image sub-sampling no analog circuit modification is required withinthe CMOS image sensor. A digital control circuit manipulates thesub-sampling addresses during the readout. For an n:1 image reductionratio, the output rate at which the imaged is transferred from the array15 is reduced to 1/n².

In image binning, binning processing is either the digital domain oranalog domain. For image binning in digital domain, an on-chipanalog-to-digital converter converts all the pixel signals to digitalvalues and store the values in a static random access memory (SRAM).Then, the stored pixel values are added digitally based on the color andnumber of pixels in the reduction window. This approach requires thatthe transfer rate of the pixel values from the SRAM to be at a higherspeed (full resolution at 30 frames per second). This further requiresthat the SRAM to be relatively very large. If the CMOS APS's array, theanalog-to-digital-converter, and the SRAM are integrated on the samesubstrate, the substrate dissipates very high power and is very large.Image binning in the analog domain, increases the complexity of analogcircuit design significantly to accomplish the real time pixel binning.

A simple image averaging can be done by changing the column sample/holdcircuit design. However, although pixel averaging gives the good spatialresolution, signal level at low light illumination condition stillresults the poor image performance.

FIG. 2 shows a typical CMOS Active Pixel Sensor (APS) of the prior art,using a photo-diode as a photo-conversion device for example. The drainterminals of the transistors M1 and M2 are connected to the power supplyvoltage distribution line, V_(DD) The source of the transistor M2 isconnected to the anode of the photo-diode D_(F). The cathode of thephoto-diode is connected to the ground reference point. The capacitanceC_(FD) is the inherent capacitance of the photo-diode D_(F).

The gate of the transistor M2 is connected to a reset terminal toreceive the reset signal V_(rst). The sensor readout node FD, that isthe anode of the photo-diode D_(F), is first reset to a high voltagelevel (V_(DD)) by changing the reset signal V_(rst) from a low voltagelevel (0) to a high voltage level (V_(DD)) to charge the capacitanceC_(FD). At the completion of charging the capacitance C_(FD), the resetsignal V_(rst) is changed from the high voltage level (V_(DD)) to thelow voltage level (0). Since light is shining on the photo-diode D_(F),photo-generated electrons are collected at node FD and the voltage atthe node FD decreases in the process. At the end of the exposureduration the voltage at node FD is measured, thus completing onephoto-sensing cycle. The photo-sensing cycle is completed by activatingthe transistor M3 by changing the row select signal from the low voltagelevel (0) to the high voltage level (V_(DD)) that reads the differentialvoltage of signal and reset level to column sample/hold circuit (S/HCKT).

The gate of the transistor M1 is connected to the node FD and the sourceof the transistor M1 is connected to the drain of the transistor M3. Thetransistor M1 acts as a source follower such that the voltage present atthe source of the transistor M1 “follows” directly the voltage presentat the gate of the transistor M1 and is one transistor threshold voltageV_(T) below the voltage present at the gate of the transistor M1.

The gate of the transistor M3 is connected to the row select line toreceive the row select signal V_(row). The source of the transistor M3is connected to the sample and hold circuit. The sample and hold circuitprovides the pixel output voltage V_(OUT) to the column bus ColBus. Thecolumn bus ColBus interconnects all the APS's present on a column of anarray of APS's. When the row select signal changes from a low voltagelevel (0V) to a high level (V_(DD)), the transistor M₃ turns-on and thevoltage present at the source of the transistor M₁ is transferred to theoutput of the APS to couple the voltage that is proportional to theintensity of the light L. The output signal V_(out) _(—) _(pixel) of theAPS is coupled to sample and hold circuit for conditioning and controlfor transfer to the column bus ColBus and to the video amplifier forfurther conditioning and readout.

The column sample and hold circuit, as shown in FIG. 2 is shown in moredetail in FIG. 3. The column sample and hold circuit combines the columnpixel row operation (pixel reset, row select) and the column operation(the photo generation, photo sensing). The clamp signal activates theswitch SW₂ to place the capacitors of CS1 and CS2 in parallel forcharging during the photo generation or conversion period of the lightsignal L to a light conversion electrical signal. The switch SW₂ is thedeactivated during the pixel reset time to provide the differentialoutput signal. This combination causes the output voltage Vout to beequal to the differential voltage of pixel reset level and photoconversion electrical signal level, i.e., V_(out)=V_(rst)−V_(sig) of allthe pixels in one row is stored in the column sample/hold circuit onseries capacitors of CS1 and CS2 of each column. During the pixelreadout, switch SW₃ controlled by column select signal COL_SEL selectsthe column output. Column output drives the VIDEO AMP that applies thegain and offset correction to the output signal. The output of VIDEO AMPis the analog output that is digitized by an analog-to-digital converter(not shown). Since column bus has fairly large parasitic capacitance(CP), the pixel output Vout has been diluted. The actual input voltageto VIDEO AMP is given by: $\begin{matrix}{V_{IN}^{{VID}\quad{AMP}} = {\frac{\left( \frac{{CS}\quad{1 \cdot {CS}}\quad 2}{{{CS}\quad 1} + {{CS}\quad 2}} \right)}{\left( \frac{{CS}\quad{1 \cdot {CS}}\quad 2}{{{CS}\quad 1} + {{CS}\quad 2}} \right) + {CP}} \cdot V_{OUT}}} & (4)\end{matrix}$

Where:

-   -   V_(IN) ^(VID AMP) is the voltage level representing the light        level impinging upon the pixel being sensed.    -   CS1 is the capacitance value of the series capacitor CS1.    -   CS2 is the capacitance value of the series capacitor CS2.    -   CP is the capacitance value of the parasitic capacitor CP.        Although the passive column output scheme dilutes the output        voltage, the column fixed pattern noise (FPN) is very low.

An alternate approach for the column sample/hold circuits isimplementing active column circuit. The active circuit in columnsample/hold approach can eliminate the signal dilution due to chargesharing in passive readout scheme. The column fixed pattern introducedby active column circuit can be minimized by a double sampling scheme.FIG. 4 shows the schematic diagram of active column sample and holdapproach.

In this approach, a source follower SF₁ is placed between the node thatdevelops the output voltage V_(OUT) and the column select switch SW₃.The source follower isolates the output voltage from the effects of thestray capacitor CP. This causes the actual input voltage to VIDEO AMP isgiven by:V_(IN) ^(VID AMP)=GV_(OUT)  (5)

Where:

-   -   G is the gain of source follower.

“Progress in Voltage and Current Mode On-Chip Analog-to-Digitalconverters for CMOS Image Sensors”, Panicacci, et al., Jan. 31, 1996,Found Jul. 13, 2004: http://techreports.jpl.nasa.gov/1996/1006.htmldescribes CMOS active pixel sensors having row and column averagingcircuits for varying the resolution of the image sensors.

“Variable Resolution CMOS Current Mode Active Pixel Sensor,” Coulombe,et al., Proceedings—The 2000 IEEE International Symposium on Circuitsand Systems—ISCAS 2000, 2000, vol. 2, pp: 293-296, a current mediatedactive pixel sensor (APS) with variable image size and resolution forpower saving, electronic zooming, and data reduction at the sensorlevel. The circuit can perform averaging of output signals in blocks ofadjacent pixels (kernels) of size 1×1, 2×2 and 4×4, allowing datareduction without aliasing effects. To achieve this, a current approachis used, thus enabling high speed operation and low power supplycapacity. The circuit compensates for pixel transconductance mismatch inaddition to offset error via analog to digital conversion referencecurrent scaling.

“Frame-Transfer CMOS Active Pixel Sensor with Pixel Binning”, Zhou, etal., IEEE Transactions on Electron Devices, October 1997 Vol.: 44,Issue: 10, pp.: 1764-1768, reports a first frame-transfer CMOS activepixel sensor (APS). The sensor architecture integrates an array ofactive pixels with an array of passive memory cells. Charge integrationamplifier-based readout of the memory cells permits binning of pixelsfor variable resolution imaging.

U.S. Pat. No. 6,721,464 (Pain, et al.) discloses a high-speed on-chipwindowed averaging system using photodiode-based CMOS imager. The systemhas an imager array, a switching network, computation elements, and adivider circuit. The imager array has columns and rows of pixels. Theswitching network is adapted to receive pixel signals from the imagearray. The plurality of computation elements operates to compute columnand row averages.

U.S. Pat. No. 5,585,620 (Nakamura, et al.) teaches an image readingdevice (image scanner) that includes a resolution changing device. Theresolution is changed by an averaging process circuit that averages thesignals output from adjacent photoelectric sensor elements. Theaveraging process circuit changes a resolution of the image by a factorof m by averaging the signals output by m adjacent photoelectric sensorelements, where m is an integer.

U.S. Pat. No. 6,166,367 (Cho) describes a programmable arithmeticcircuit to form multiple circuit modules for different arithmeticoperations that share certain common electronic elements to reduce thenumber of elements. Such circuit can be integrated to an imaging sensorarray such as a CMOS active pixel sensor array to perform arithmeticoperations and analog-to-digital conversion for imaging processing suchas pixel averaging for resolution reduction.

U.S. Pat. No. 6,104,844 (Alger-Meunier) teaches an image sensor that hasadjustable resolution. Neighboring sensor elements are in each casecombined into pixel sensor regions. During the recording of the image,the measured values of the sensor elements of each sensor region areaveraged. In this case, each average value corresponds to a pixel of therecorded image. In this manner, production-dictated tolerances of thesensor elements are compensated for by the averaging.

SUMMARY OF THE INVENTION

An object of this invention is to provide an apparatus for adjusting theresolution of an array of image sensors such as CMOS active pixelsensors.

Another object of this invention is to provide an apparatus foradjusting the resolution of an array of image sensors while maintaininghigh image quality.

Still further, another object of this invention is to provide anapparatus for adjusting the resolution of an array of image sensors thathorizontally averages sub-groups of the image sensors.

Still, another object of this invention is to provide an apparatus foradjusting the resolution or an array of image sensors that verticallyaverages sub-groups of the image sensors in high light level.

To accomplish at least one of these objects, a photo-sensor imageresolution adjustment apparatus is in communication with an array ofimage photo-sensors. The array of image photo-sensors is organized incolumns and rows and has multiple sensor types arranged in a patternsuch as a Bayer pattern to detect light. Each sensor type detects uniquecolors of the light and converts the light to a light conversionelectrical signals. The photo-sensor image resolution adjustmentapparatus adjusts sensor resolution for reception of the light.

The photo-sensor image resolution adjustment apparatus has aphoto-sensor array decimation circuit. The photo-sensor array decimationcircuit is in communication with an addressing control circuitry of thearray of image photo-sensors to partition the array of imagephoto-sensors into a plurality of sub-groups of the array of imagephoto-sensors and provide partition control signals. A column averagingcircuit is in communication with the array of image photo-sensors toreceive the light conversion electrical signals and in communicationwith the photo-sensor array decimation circuit to receive the partitioncontrol signals. From the partition control signals the column averagingcircuit averages the light conversion electrical signals fromphoto-sensors detecting common colors from the columns of each of theplurality of the sub-groups of the array of image photo-sensors tocreate column averaged electrical signals of the columns of theplurality of the sub-group of the array of image photo-sensors.

The column averaging circuit has a plurality of even averagingcapacitors. Each even averaging capacitor is connected to receive thelight conversion electrical signal from the common color adjacentphoto-sensors of the array of image photo-sensors on the columns. Thecommon color adjacent photo-sensors are at one set of columns is ofcommon color photo-sensors detects red (R) and the alternate column ofcommon color photo-sensors detects green-1 (G1). Each of a plurality ofeven averaging switches is connected to receive the light conversionelectrical signals from the common color adjacent photo-sensors on thecolumns to selectively transfer the light conversion electrical signalsfrom the common color adjacent photo-sensor to a selected even averagingcapacitor to average the light conversion electrical signals from anattached photo-sensor and the common color adjacent photo-sensors. Eachof the plurality of even averaging switches is in communication with thetiming and control circuit to receive the timing, control, and selectsignals to selectively connect one the even averaging capacitors toaverage the light conversion electrical signals of the common colorassociated photo-sensors of the array of image photo-sensors on thecolumns.

The column averaging circuit, additionally, has a plurality of oddaveraging capacitors. Each odd averaging capacitor is connected toreceive the light conversion electrical signal from the common coloradjacent photo-sensors of the array of image photo-sensors on thecolumns. The common color adjacent photo-sensors are at one set ofcolumns is of common color photo-sensors detects green-2 (G2) and thealternate column of common color photo-sensors detects blue (B). Each ofa plurality of odd averaging switches is connected to receive the lightconversion electrical signals from the common color adjacentphoto-sensors on the columns to selectively transfer the lightconversion electrical signals from the common color adjacentphoto-sensor to a selected odd averaging capacitor to average the lightconversion electrical signals from an attached photo-sensor and thecommon color adjacent photo-sensors. Each of the plurality of oddaveraging switches is in communication with the timing and controlcircuit to receive the timing, control, and select signals toselectively connect one the odd averaging capacitors to average thelight conversion electrical signals of the common color associatedphoto-sensors of the array of image photo-sensors on the columns.

The photo-sensor image resolution adjustment apparatus has a timingcontrol circuit in communication with the photo-sensor array decimationcircuit and the column averaging circuit to provide timing, control, andselect signals. The timing, control, and select signals coordinategeneration of the light conversion electrical signals from the pluralityof sub-groups of the array of image photo-sensors, averaging of thelight conversion electrical signals from selected sensors within thesub-group to create the column averaged electrical signals.

A sample and hold circuit within the photo-sensor image resolutionadjustment apparatus is connected to the array of image photo-sensors tosample and hold the light conversion electrical signals from selectedphoto-sensors. The sampled and held light conversion electrical signalsare then transferred to the column averaging circuit. The sample andhold circuit is in communication with the timing and control circuit toreceive the timing, control, and select signals for sampling and holdingthe light conversion electrical signals.

The photo-sensor image resolution adjustment apparatus further includesa row averaging circuit in communication with the column averagingcircuit to receive the column averaged electrical signals of eachsub-group of photo-sensors that detect the common colors arranged on thecolumns within each sub-group of the array of image photo-sensors. Therow averaging circuit is also in communication with the photo-sensorarray decimation circuit to receive the partition control signals. Fromthe partition control signals, the row averaging circuit averages thecolumn averaged electrical signals for sensors having the common colorson rows of each of the plurality of the sub-groups of the array of imagephoto-sensors to create row averaged electrical signals of the rows ofthe plurality of the sub-group of photo-sensors having common colors ofthe array of image photo-sensors. The row averaging circuit is incommunication with the timing and control circuit to receive the timing,control, and select signals for creating the row averaged electricalsignals.

The row averaging circuit has a plurality of row averaging switches.Each row averaging switch is connected to the column averaging circuitto receive column averaged electrical signals for sensors with thecommon colors on the rows of each of the plurality of sub-groups of thearray of image photo-sensors to average the column averaged lightconversion electrical signals to create the row averaged electricalsignals. Each of the plurality of row averaging switches is incommunication with the timing and control circuit to receive the timing,control, and select signals to selectively connect the column averagingcircuits of sensors having the common colors on the rows of each of theplurality of sub-groups of the array of image photo-sensors for theaveraging.

The photo-sensor image resolution adjustment apparatus further includesa video amplifier connected to selectively receive one of a group ofelectrical signals consisting of the light conversion electrical signalsand the row averaging electrical signals to amplify and condition theselected electrical signals for external processing.

The photo-sensor image resolution adjustment apparatus optionally has aplurality of source follower circuits. Each source follower is connectedto receive one of the light conversion electrical signals and the columnaveraged electrical signals to isolate the received one of the lightconversion electrical signals and the column averaged electrical signalsor row averaged electrical signals from effects of a parasitic capacitorpresent at an output bus of the photo-sensor image resolution adjustmentcircuit. If the photo-sensor image resolution adjustment apparatus doesnot have the plurality of source follower circuits, it considered apassive column averaging, row binning or averaging resolution adjustmentcircuit. The isolation of the plurality of even and odd averagingcapacitors from the row binning circuit with the source followerconverts the photo-sensor image resolution adjustment apparatus to acolumn averaging, row averaging or binning circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 a and 1 b are diagrams illustrating a Bayer patterned colorimage sensor array demonstrating sub-sampling for adjusting resolutionof image sensor array of the prior art.

FIG. 2 is a schematic diagram of an image sensor with a sample and holdcircuit of the prior art.

FIG. 3 is a schematic diagram of the sample and hold circuit of FIG. 2.

FIG. 4 is a schematic diagram of the sample and hold circuit of FIG. 2with a source follower to isolate the sample and hold circuit fromparasitic capacitances of the Column Bus.

FIG. 5 is block diagram of an image sensor of this invention with animage resolution adjustment circuit.

FIG. 6 a is a schematic diagram of a first embodiment of a single columnsample, holding, and averaging sub-circuit of an image resolutionadjustment circuit of this invention.

FIG. 6 b is a schematic diagram of the storage capacitor reset signalsub circuit of the single column sample, holding, and averagingsub-circuit of an image resolution adjustment circuit of this invention,as shown in FIG. 6 a.

FIG. 6 c is a schematic diagram of the video amplifier/switchedcapacitor integrator circuit of an image resolution adjustment circuitof this invention, as shown in FIG. 6 a.

FIG. 7 is a timing diagram of a second embodiment of a single columnsample, holding, and averaging sub-circuit of an image resolutionadjustment circuit of this invention, as shown in FIG. 6 a.

FIG. 8 is a schematic diagram a simplification of the first embodimentof a single column sample, holding, and averaging sub-circuit of animage resolution adjustment circuit of this invention, as shown in FIG.6 a.

FIG. 9 is a diagram of the composite relationship of FIGS. 9 a-9 d.

FIGS. 9 a-9 d are, in composite, a schematic diagram of multiple asingle column sample, holding, and averaging sub-circuits forming theimage resolution adjustment circuit of this invention.

FIG. 10 is a diagram of the composite relationship of FIGS. 10 a-10 b.

FIGS. 10 a-10 b are timing diagrams for operation of the imageresolution adjustment circuit of this invention of FIGS. 9 a-9 d showingcolumn averaging for a 2:1 decimation for the image resolutionadjustment.

FIG. 11 is a diagram of the contents of the averaging capacitors ofFIGS. 9 a-9 d for the 2:1 decimation for the image resolutionadjustment.

FIG. 12 is a diagram of the composite relationship of FIGS. 12 a-12 c.

FIGS. 12 a-12 c are timing diagrams for operation of the imageresolution adjustment circuit of this invention of FIGS. 9 a-9 d showingcolumn averaging for a 3:1 decimation for the image resolutionadjustment.

FIG. 13 is a diagram of the contents of the averaging capacitors ofFIGS. 9 a-9 d for the 3:1 decimation for the image resolutionadjustment.

FIG. 14 is a diagram of the composite relationship of FIGS. 14 a-14 c.

FIGS. 14 a-14 c are timing diagrams for operation of the imageresolution adjustment circuit of this invention of FIGS. 9 a-9 d showingcolumn averaging for an n:1 decimation for the image resolutionadjustment.

FIG. 15 is a diagram of the contents of the averaging capacitors ofFIGS. 9 a-9 d for the n:1 decimation for the image resolutionadjustment.

FIG. 16 is a diagram of the composite relationship of FIGS. 16 a-16 c.

FIG. 16 a-16 c are, in composite, a timing diagram for operation of theimage resolution adjustment circuit of this invention of FIGS. 9 a-9 dshowing the image resolution adjustment for providing vertical rowaveraging for an n:1 decimation for the image resolution adjustment.

FIG. 17 is a diagram of the composite relationship of FIGS. 17 a-17 c.

FIGS. 17 a-17 c are, in composite, timing diagrams for operation of theimage resolution adjustment circuit of this invention of FIGS. 9 a-9 dshowing vertical row binning for an n:1 decimation for the imageresolution adjustment.

FIG. 18 is a timing diagram for operation of the image resolutionadjustment circuit of this invention of FIGS. 9 a-9 d showing the imageresolution adjustment for providing the full frame resolution of theimage sensor.

FIG. 19 is a schematic diagram of a second embodiment of a single columnsample, holding, and averaging sub-circuit of an image resolutionadjustment circuit of this invention.

FIG. 20 is a diagram of the composite relationship of FIGS. 20 a-20 d.

FIGS. 20 a-20 d are, in composite, a schematic diagram of multiple asingle column sample, holding, and averaging sub-circuits forming theimage resolution adjustment circuit of this invention.

DETAILED DESCRIPTION OF THE INVENTION

The CMOS active pixel sensor array of this invention achieves highspatial resolution in the analog domain and high image quality at lowlight level by a horizontal (column) pixel averaging and vertical (row)pixel binning approach for Bayer patterned pixel array. Additionally,the CMOS active pixel sensor array of this invention achieves highspatial resolution in the analog domain and high image quality at highlight level by a horizontal (column) and vertical (row) pixel averagingapproach for Bayer patterned pixel array. The advantages of the CMOSactive pixel sensor array of this invention are a simple analog columnsample and hold circuit; a reduced pixel output rate for decimated imageto achieve low power operation; no additional on-chip memory required;and a scalability to any pixel array decimation ratio.

As shown in FIG. 5, an array of color CMOS APS image sensors 100 isarranged in rows and columns. The array 100 is formed of three types ofCMOS APS image sensor pixels by using different color filters. The firsttype of CMOS APS image sensor is fabricated to sensitive to red light,the second type of CMOS APS image sensor is fabricated to be sensitiveto blue light, and the third type of CMOS APS image sensor is fabricatedto be sensitive to green light. The CMOS APS image sensors are organizedin the Bayer pattern (U.S. Pat. No. 3,971,065). The pattern has a singlered sensor 102, a single blue sensor 105, and two green sensors 104 and108.

A row address decoder 115 receives a row address 110 to select a row ofthe CMOS active pixel sensors for activation. The light conversionelectrical signals resulting from the conversion of the light as shownin FIG. 2 from the selected row of active pixel sensors are transferredto a sample and hold circuit 125 that samples and holds the lightconversion electrical signal. A column address decoder 140 receives acolumn address 145 select one of the sampled and held light conversionelectrical signals from a desired active pixel sensor for transfer tothe video amplifier/switched capacitor integrator circuit 170 togenerate the analog video output signal 175.

For full resolution operation, the sampled and held light conversionsignal is transferred to bypass the column averaging circuit 130 and therow averaging circuit 135. To adjust the resolution of the array ofactive pixels sensors 100 to reduce the resolution, the decimationcircuit 150 receives a decimation ratio signal 155. The decimationcircuit generates the necessary address partition signals that arerequired to partition or decimate the addressing of the array of activepixel sensors 100 to create sub-groups of active pixels sensors thatwill act as super-pixels. The number of super-pixels being asub-multiple of the number of pixels within the array of active pixelssensors 100. For example digital video cameras that employ imagessensors with SXGA image format have 1280×1024 pixel sensor, orapproximately 1.3 million pixels or with QXGA image format have2048×1536 pixels, or approximately 3.2 million pixels. The view findersof these cameras generally use the Common Intermediate Format (CIF). TheCIF format is a video format used in videoconferencing systems thateasily supports both NTSC and PAL signals. CIF specifies a data rate of30 frames per second (fps), with each frame containing 288 lines and 352pixels per line (352×288). A digital camera must decimate or divide thearray of active pixels sensors 100 of a SXGA formatted image array by adecimation ratio of 3:1. Similarly, a digital camera must decimate thearray of active pixel sensors 100 of a QXGA formatted image array by adecimation ratio of 5:1.

To perform the pixel binning/averaging of the color image, two rows ofimage information, i.e., R/G1 row and G2/B row must be retained. Asub-group of the pixels are formed into super-pixels. Each super-pixelhas a size equal to (2n)×(2n) for an n:1 decimation ratio. In theoperation, the output color patterns, R^(O), G1^(O), G2^(O), and B^(O),are produced by all the information from the Bayer pattern in thesuper-pixel. In other words, for an n:1 image decimation ratio, imagepixels in the (2 n)×(2 n) super-pixel window will is combined to a 2×2Bayer pattern with single R^(O), G1^(O), G2^(O), and B^(O) values.

The decimation signal 145 thus provides a coding to indicate thedecimation ratio necessary to divide the array of active pixel sensorsinto sub-groups of super-pixels for the sub-multiple format. Thedecimation circuit 150 then provides the necessary address controls suchthat the row address 110 and the column address 145 not only selects aparticular row and column to designate a particular image sensor, butalso to select the appropriate neighboring image sensors within thesuper-pixel. The column averaging circuit 130 receives the sampled andheld light conversion electrical signals from the columns of a centralrow of the addressed row of super-pixels. The sampled and held lightconversion electrical signals of the neighboring image sensors areaveraged with the central column of the sub-group of image sensorsforming the super-pixel. In high intensity light operations, theneighboring rows of the addressed row of super-pixels are selected andthe neighboring columns are averaged and transferred to the rowaveraging circuit 135. The averaged electrical signals of the addressedcolumn of the super-pixels for each row of the addressed row of thesuper-pixels are averaged to create the high light conversion electricsignal for the super-pixel. The column address circuit 140 selects thehigh light conversion electric signal for a desired addressed column ofthe super-pixel for transfer to the video amplifier/switched capacitorintegrator circuit 170 to generate the analog video output signal 175.The analog video output signal 175 being transferred to externalcircuitry such as an analog-to-digital converter for further processing.In low light operations, the row averaging circuit 135 is deactivatedand the column address circuit 140 transfers the column averaged lightconversion electrical signal to the video amplifier/switched capacitorintegrator circuit 170. The video amplifier/switched capacitorintegrator circuit 170 integrates the column averaged light electricalsignals to bin the physical pixels signals to form the binning on lowlight conversion electric signal for each super-pixel.

The address, timing, and control processor circuit 165 address, timing,and control processor circuit 165 generates the necessary row address110, column address 145, timing, and control signals to select andactivate the decimation circuit 150, the row address decoder 115, thesample and hold circuit 125, the column averaging circuit 130, the rowaveraging circuit 135, column address decoder 140 and videoamplifier/switched capacitor integrator circuit 170. The address,timing, and control processor circuit 165 generates the row address 110,column address 145 for capturing the light conversion electrical signalsfrom the array of active pixel sensors 100 either passing these signalsdirectly to the generate the video signals or decimating the videosignal for reduced resolution of the image from the array of activepixel sensors 100.

Refer now to FIG. 6 a for a discussion of the structure of the sampleand hold circuit 125, the column averaging circuit 130, and the rowaveraging circuit 135 for one column of the array of active pixelsensors. The output terminal PIX_OUT provides the output current I_(PIX)from an active pixel sensor of a selected row of the array of activepixel sensors 100 of FIG. 5. The structure and operation of sample andhold circuit 125 is fundamentally that of the sample and hold circuit ofFIG. 3.

The sample and hold switch SW₁ samples the conversion signal and resetvoltage level of the output of the pixel of the selected row. The sampleand hold switch SW₁ is controlled by the sample and hold signal SH. Theclamp switch SW₂ provides the clamping of the signal level in signalsampling phase and is controlled by the clamping signal CLAMP.

Referring to FIGS. 2, 5, 6 and 7 for an explanation of the operation ofthe sample and hold circuit 125. The row decoder 115 decodes the rowaddress signal 110 containing a row address ROW_ADDR[N:0] of the desiredrow (i) of the array. The row select signal ROW_SEL provides the timingto activate the transistor M3 of the active pixel sensor to transfer theconversion signal and reset voltage level to the input terminal PIX_OUTof the sample and hold circuit 125. The pixel reset sampling timePIX_RST resets the pixel after the signal has been sampled. The sampleand hold signal SH activates the switch SW₁ to transfer the differentialvoltage of pixel reset and signal conversion level to the serialcapacitors of CS1 and CS2. The clamp signal activates the switch SW₂ toplace the capacitors of CS1 and CS2 in parallel for charging during thesignal sampling period. The switch SW₂ is the deactivated during thepixel reset sampling time PIX_RST to provide the differential lightconversion electrical output signal V_(OUT).

The column averaging circuit 130 combines the light conversionelectrical signals from the sample and hold circuits of same colorpixels in adjacent columns of the selected row to average the lightconversion signals. The number of pixels being averaged is dependant onthe image decimation ratio. The column average switch SW₄ connects lightconversion signal V_(OUT) from the same color pixels of the next coloradjacent column of the selected connected to the terminal VNC and iscontrolled by column averaging signal COL_AVE. The terminal VPC connectsto the switch SW₄ of the averaging circuit associated with the samecolor pixel of the previous adjacent column of the selected row.

During the readout time the capacitors of CS1 and CS2 are seriallyconnected to provide the sampled and held light conversion signal forthe pixel (differential voltage level of pixel signal and reset level)connected to the sample and hold circuit 125 on the selected row. Thecolumn averaging signal COL_AVE connects the serially connectedcapacitors of CS1 and CS2 of the adjacent same color pixels. The outputvoltages V_(OUT) from the connected serially connected capacitors of CS1and CS2, when the column averaging switches SW₄ are activated, causesthe resulting voltage to be averaged.

The averaged differential output signal V_(OUT) is applied to the evenrow signal transfer switch SW₅ and odd row signal transfer switch SW₆.The even row signal transfer switch SW₅ transfers the differentialoutput signal V_(OUT) Of even rows (after column averaging) to storagecapacitor CE. The store even row signal at the terminal ST_EVEN selectsthe differential output signal V_(OUT) from the pixel on the column of aselected even row of pixels within the super-pixel being evaluated. Theodd row signal transfer switch SW₆ transfers the differential outputsignal V_(OUT) of odd rows (after column averaging) to storage capacitorCO. The store odd row signal at the terminal ST_ODD selects thedifferential output signal V_(OUT) from the pixel on the column of aselected odd row of pixels within the super-pixel being evaluated. Asshown in FIG. 6 b, the storage capacitors CE and CO are initialized byhaving any residual charge transferred to ground through the switchesSW₁₁ and SW₁₂. The storage capacitor reset signal CECO_RST whenactivated sets the switches SW₁₁ and SW₁₂ to connect the storage platesof storage capacitors CE and CO to the analog ground reference terminal.When the storage capacitors CE and CO are reset, the storage capacitorreset signal CECO_RST is deactivated.

In a reduced resolution mode, as described above, a row selected at thereduced resolution includes all the rows of the actual physical array ofactive pixel sensors within each super-pixel. Thus the time for each ofthe reduced resolution rows of the active pixel sensors must average thecolumns of each physical row and then combine the physical rows of thesuper-pixel to bin the results.

In high level light conditions, the row averaging circuit 135 averagesthe average differential output signal V_(OUT) for the same color pixelsof the adjacent rows. The even row average switch SW₉ connects thedifferential output signal V_(OUT) of the currently selected column tothe terminal VNR_EVEN of the next adjacent row of same color columnaveraged pixels to average the two differential output signals V_(OUT)of the two rows. The terminal VPR_EVEN that is connected to the even rowaverage switch SW₉ of the previous row of same color column averagedpixels. If the even row average switch SW₉ is activated, the columnaveraged pixels of the previous row are averaged with the selected rowand the next row. The even row average control signal RAVE_EVEN isselected by the row address decoder 115 and the decimation circuit 150of FIG. 5 to select the averaging of the selected rows of thesuper-pixel during high-light level conditions. The odd row averageswitch SW₁₀ connects the differential output signal V_(OUT) of thecurrently selected column to the terminal VNR_ODD of the next adjacentrow of same color column averaged pixels to average the two differentialoutput signals V_(OUT) of the two rows. The terminal VPR_ODD that isconnected to the odd row average switch SW₁₀ of the previous row of samecolor column averaged pixels. If the odd row average switch SW₁₀ isactivated, the column averaged pixels of the previous row are averagedwith the selected row and the next row. The odd row average controlsignal RAVE_ODD is selected by the row address decoder 115 and thedecimation circuit 150 of FIG. 5 to select the averaging of the selectedrows of the super-pixel during high-light level conditions.

In low light conditions the physically adjacent even rows or physicallyadjacent odd rows are combined to integrate or bin the magnitude of thedifferential output signals V_(OUT) of the adjacent same color columnsof the super-pixel. FIG. 6 c shows a switch capacitor approach for anembodiment of the video amplifier/switched capacitor integrator circuit170. Other approaches, such as fully differential switch capacitordesign, can be implemented and still be in keeping with the intent ofthis invention.

The column bus parasitic capacitance CP is at the input of the videoamplifier/switched capacitor integrator circuit 170. The input signal ofthe video amplifier/switched capacitor integrator circuit 170 is thecolumn voltage V_(col) and is applied to the sampling switch SW₁₃. Thefirst sampling switch control signal SMPL1, when activated, allows thecolumn voltage V_(col) from the selected source follower SF₁, SF₂, orSF₃ to charge the sampling capacitor CSMPL to the signal level VA_(in).The sampling capacitor CSMPL is connected to on one terminal of thesecond sampling control switch SW₁₄ and to the inverting terminal of theoperational amplifier A and the top plate of the feedback capacitor CFBon the second terminal. The bottom plate of the feedback capacitor CFBis connected to the output of the operational amplifier A.

The feedback capacitor reset switch SW₁₅ is in parallel with thefeedback capacitor CFB to remove accumulated charge. The commonreference voltage VCM is connected to the noninverting terminals of theoperational amplifier A. During the activation of the first samplingswitch control signal SMPL1, the feedback capacitor reset switch SW₁₅ isactivated by the reset control pulse RST_CFB resets (input and output ofthe OPAMP) to common voltage VCM to remove any charge from the feedbackcapacitor CFB.

When the first sampling switch control signal SMPL1 and reset controlpulse RST_CFB are deactivated, the second sampling control signal SMPL2second sampling control switch SW₁₄ is activated to transfer charge fromsampling capacitor CSMPL to the feedback capacitor CFB. The outputvoltage VA_(out) of operational amplifier A is given by:${V\quad A_{OUT}} = {{VCM} - {{\frac{CSMPL}{CFB} \cdot V}\quad{A_{IN}.}}}$The video amplifier/switched capacitor integrator circuit 170 of theshown embodiment gives proper analog gain to the signal. The ratio ofthe sampling capacitor CSMPL to the feedback capacitor CFB (CSMPL/CFB)determines the analog gain. An embodiment with programmable analog gaincan be designed by programming the sampling capacitor CSMPL. Thesampling capacitor CSMPL in this instance is has a multiple selectablesegment capacitors to adjust the gain.

If the resolution of the array of CMOS active pixel sensors is notadjusted, the differential output signal V_(OUT) of each pixel isreadout directly to the source follower SF₁. The column select switchSW₃, selects the source follower SF₁ output in high resolution imagingmode (i.e. no column pixel averaging or row averaging or binning) and iscontrolled by the column select signal COL_SEL.

If the array of CMOS active pixel sensors is adjusted for a lowerresolution, the averaged differential output signal V_(OUT) present onthe even averaging capacitor CE is transferred through the sourcefollower SF₂. The source follower SF₂ isolates the differential outputsignal V_(OUT) from the effects of the parasitic capacitor 180 of thecolumn bus. The even column select switch SW₇ selects the sourcefollower SF₂ output for even column averaging signal. The column addressdecoder 140 activates the switch SW₇ with the even column select switchsignal CSEL_EVEN. Similarly, the averaged differential output signalV_(OUT) present on the odd averaging capacitor CE is transferred throughthe source follower SF₃. The source follower SF₃ isolates thedifferential output signal V_(OUT) from the effects of the parasiticcapacitor 180 of the column bus. The odd column select switch SW₈selects the source follower SF₃ output for odd column averaging signal.The column address decoder 140 activates the switch SW₈ with the oddcolumn select switch signal CSEL_ODD. The average differential outputsignal V_(OUT) as transferred through the source follower SF₁, sourcefollower SF₂, or source follower SF₃ is transferred as the columnvoltage V_(COL) to the column bus COL_BUS to the videoamplifier/switched capacitor integrator circuit 170.

Referring now to FIG. 8, the effective circuit of sample and holdcircuit 125 after the pixel sample and hold phase as shown in FIG. 6. Inthe effective circuit of the sample and hold circuit, the capacitor CSis the serial capacitor of capacitors CS1 and CS2. (i.e.,CS=(CS1*CS2)/CS1+CS2). The differential output signal VOUT is dependentupon the operation rows and columns and can be the output of red (R),green-1 (G1), green-2 (G2), or blue (B) pixel for a selected row andcolumn.

FIGS. 9 a-9 d, in composite, illustrate multiple sections of the columnsample and hold 125 column averaging circuit 130, the row averagingcircuit 135, and the source followers SF1, SF2, and SF3 that hereinafterare referred to as the Sample and Hold Column Averaging Circuit (SHCAC).Each section is connected to receive the light conversion electricalsignal from a CMOS active pixel sensor on a selected row of one columnof CMOS active pixel array sensors. FIGS. 9 a-9 d show, by example theeffective column SHCAC block shown of FIG. 8 for twelve columns (fromcolumn (i) to column (i+11)). Each of the effective column SHCAC blocksas shown function as described for the sample and hold circuit 125, thecolumn averaging circuit 130, and the row averaging circuit 135 of FIG.6. For an n:1 ratio image decimation, the individual pixels are combinedby the decimation circuit 150 of FIG. 5 into super-pixels having 2nphysical columns and 2n physical rows of pixels that define the columnsand rows of the super-pixels. Each super-pixel includes n red (R), ngreen-1 (G1), n green-2 (G2), and n blue (B) pixels. The averaging andbinning operations of the pixels in the super-pixel gives the effectivered (R), green-1 (G1), green-2 (G2), and blue (B) signals for each Bayerpatterned supper-pixel set.

To illustrate the operation of column averaging and row binning oraveraging, the operation of the SHCAC of FIGS. 9 a-9 d will be explainedusing a decimation ratio of 2:1 in a first example and for a decimationratio of 3:1 in a second example. For the decimation ratio of 2:1, thecolumn and rows of each super-pixel starts at the physical column androw addresses that are a multiple of the decimation ratio. In a Bayerpatterned array of CMOS active pixel sensors, the evaluation todetermine the magnitude of the colors of each of the super-pixelsrequires that twice the decimation ratio (n) of physical rows andcolumns (2n=4, where n=2). By setting the column counter to i=4k in thesection of column SHCAC block shown in FIGS. 9 a-9 b, physical column irepresents the start column of the super-pixel column. At this setting,columns 4k, 4k+1, 4k+2, and 4k+3 cover the range of kth super-pixelcolumn in the column direction of the array of CMOS active pixelsensors. Columns 4(k+1)=4k+4, 4(k+1)+1, 4(k+1)+2, and 4(k+1)+3 cover therange of (k+1)th super-pixel column in the physical column direction.FIGS. 10 a and 10 b provide the waveforms that demonstrate the analogsignal process for the averaging of the physical columns of thesuper-pixel columns of the lth and (l+1)th super-pixel row of the arrayof CMOS active pixel sensors. At the 2:1 image decimation ratio, the lthrow of super-pixel includes rows 4l, 4l+1, 4l+2, and 4l+3 and the(l+1)th row of super-pixel includes rows 4(l+1)=4l+4, 4l+5, 4l+6, and4l+7.

As described above, the column averaging operation is controlled by thecolumn averaging switches SW₄, even row signal transfer switch SW₅, andodd row signal transfer switch SW₆ in each column SHCAC circuit. Thecolumn averaging switches SW₄, even row signal transfer switch SW₅, andodd row signal transfer switch SW₆ are programmed ON/OFF depending onthe image decimation ratio (n). The waveforms in FIGS. 10 a and 10 bshow the activation signals for the column averaging switches SW₄, evenrow signal transfer switch SW₅, and odd row signal transfer switch SW₆.The row addresses ROW_ADDR[N:0] for the l^(th) row of a super-pixel byaddressing the physical row 4+l, 4l+1, 4l+2, and 4l+3 which are thenreadout during the readout period.

At the beginning of the evaluation of the lth row of the super-pixel,all the even and odd storage capacitors CE(i) and CO(i) are reset, asdescribed in FIG. 6 b, by the global reset signal CECO_RST. The resetpulse CECO_RST is given after the readout period of the information of(l−1)th super-pixel row. The row addresses ROW_ADDR[N:0] are set toaddress the desired physical row of the lth row of the super-pixel. Therow select signal ROW_SEL, the sample and hold signal SH, the clampsignal CLAMP, and the pixel reset signal PIX_RST are activated as shownin FIG. 7 to convert the light signal integrated in the pixel to thedifferential light conversion electrical output signal VOUT(i).

The averaging of the columns of the first super-pixel row l begins withthe column averaging of the first and second red (R) pixels of the evenrow 4l by setting the column averaging signal COL_AVE[4 k] to activatethe column averaging switch SW4 to connect the storage capacitor CS(i)in parallel with the storage capacitor CS(i+2) to average the first andsecond red (R) pixel signals of pixel [4k, 4l] and pixel[4k+2, 4l]. Thestore even activation signal ST_EVEN[4 k] is set to activate the evenrow signal transfer switch SW5 to transfer and store the averaging lightconversion signal of the first pixel of the lth row of the super-pixelon capacitor CE[4 k].

Simultaneously, the column averaging of the first and second green-1(G1) pixels of the super-pixel of the even row 4l is accomplished bysetting the column averaging signal COL_AVE[4 k+1] to activate thecolumn averaging switch SW4 to connect the storage capacitor CS(i+1) inparallel with the storage capacitor CS(i+3) to average the first andsecond green-1 (G1) pixel signals of pixel [4k+1, 4l] and pixel[4k+3,4l]. The store even activation signal ST_EVEN[4 k+1] is set to activatethe even row signal transfer switch SW5 to transfer and store theaveraging light conversion signal of the second pixel of the lth row ofthe super-pixel on capacitor CE[4 k+1].

The column averaging of the third and fourth red (R) pixels of the evenrow 4l by setting the column averaging signal COL_AVE[4(k+1)] toactivate the column averaging switch SW4 to connect the storagecapacitor CS(i+4) in parallel with the storage capacitor CS(i+6) toaverage the third and fourth red (R) pixel signals of pixel [4(k+1), 4l]and pixel[4(k+1)+2, 4l]. The store even activation signalST_EVEN[4(k+1)] is set to activate the even row signal transfer switchSW5 to transfer and store the averaging light conversion signal of thethird pixel of the lth row of the super-pixel on capacitor CE[4(k+1)].

The column averaging of the third and fourth green-1 (G1) pixels of thesuper-pixel of the even row 4l is accomplished by setting the columnaveraging signal COL_AVE[4(k+1)+1] to activate the column averagingswitch SW4 to connect the storage capacitor CS(i+5) in parallel with thestorage capacitor CS(i+7) to average the first and second green-1 (G1)pixel signals of pixel [4(k+1)+1, 4l] and pixel[4(k+1)+3, 4l]. The storeeven activation signal ST_EVEN[4(k+1)+1] is set to activate the even rowsignal transfer switch SW5 to transfer and store the averaging lightconversion signal of the second pixel of the lth row of the super-pixelon capacitor CE[4(k+1)+1].

The row select signal ROW_SEL is activated to select the second physicalrow 4l+1 of the first super-pixel row l. The sample and hold signal SH,the clamp signal CLAMP, and the pixel reset signal PIX_RST are activatedas shown in FIG. 7 to convert the light signal to the differential lightconversion electrical output signal VOUT(i) and transfer thedifferential light conversion electrical output signal VOUT(i) to thestorage capacitor CS(i) for each column (i).

The averaging of the first and second green-2 (G2) pixels of the odd row4l+1 by setting the column averaging signal COL_AVE[4 k] to activate thecolumn averaging switch SW4 to connect the storage capacitor CS(i) inparallel with the storage capacitor CS(i+2) to average the first andsecond green-2 (G2) pixel signals of pixel [4k, 4l+1] and pixel[4k+2,4l+1]. The store odd activation signal ST_ODD[4 k] is set to activatethe odd row signal transfer switch SW5 to transfer and store theaveraging light conversion signal of the first pixel of the lth row ofthe super-pixel on capacitor CO[4 k].

The column averaging of the first and second blue (B) pixels of thesuper-pixel of the odd row 4l+1 is accomplished by setting the columnaveraging signal COL_AVE[4 k+1] to activate the column averaging switchSW4 to connect the storage capacitor CS(i+1) in parallel with thestorage capacitor CS(i+3) to average the first and second blue (B) pixelsignals of pixel [4k+1, 4l+1] and pixel[4k+3, 4l+1]. The store oddactivation signal ST_ODD[4 k+1] is set to activate the odd row signaltransfer switch SW5 to transfer and store the averaging light conversionsignal of the second pixel of the lth row of the super-pixel oncapacitor CO[4 k+1].

The column averaging of the third and fourth green-2 (G2) pixels of theodd row 4l+1 by setting the column averaging signal COL_AVE[4(k+1)] toactivate the column averaging switch SW4 to connect the storagecapacitor CS(i+4) in parallel with the storage capacitor CS(i+6) toaverage the third and fourth green-2 (G2) pixel signals of pixel[4(k+1), 4l+1] and pixel[4(k+1)+2, 4l+1]. The store odd activationsignal ST_ODD[4(k+1)] is set to activate the odd row signal transferswitch SW5 to transfer and store the averaging light conversion signalof the third pixel of the lth row of the super-pixel on capacitorCO[4(k+1)].

The column averaging of the third and fourth blue (B) pixels of thesuper-pixel of the odd row 4l+1 is accomplished by setting the columnaveraging signal COL_AVE[4(k+1)+1] to activate the column averagingswitch SW4 to connect the storage capacitor CS(i+5) in parallel with thestorage capacitor CS(i+7) to average the first and second green-1 (G1)pixel signals of pixel [4(k+1)+1, 4l] and pixel[4(k+1)+3, 4l]. The storeodd activation signal ST_ODD[4(k+1)+1] is set to activate the odd rowsignal transfer switch SW5 to transfer and store the averaging lightconversion signal of the second pixel of the lth row of the super-pixelon capacitor CO[4(k+1)+1].

The even and odd storage capacitors CE(i) and CO(i), CE(i+1) and CO(i+1)CE(i+4) and CO(i+4), CE(i+5) and CO(i+5) store the differential lightconversion electrical output signal VOUT for the averaged columns of thefirst and second rows of the lth row of super-pixels. Likewise, as shownin the following, the even and odd storage capacitors CE(i+2) andCO(i+2), CE(i+3) and CO(i+3), CE(i+6) and CO(i+6), CE(i+7) and CO(i+7)store the differential light conversion electrical output signals VOUTfor the averaged columns of the third and fourth rows of the lth row ofsuper-pixels.

The row addresses ROW_ADDR[N:0] are set to address the desired physicalrow (4l+2) of the lth row of the super-pixel. The row select signalROW_SEL, the sample and hold signal SH, the clamp signal CLAMP, and thepixel reset signal PIX_RST are activated as shown in FIG. 7 to convertthe light signal to the differential light conversion electrical outputsignal VOUT(i) for each of the columns.

The averaging of the columns of the row of pixels l+2 begins with thecolumn averaging of the first and second red (R) pixels of the even row4l+2 by setting the column averaging signal COL_AVE[4 k+2] to activatethe column averaging switch SW4 to connect the storage capacitor CS(i)in parallel with the storage capacitor CS(i+2) to average the first andsecond red (R) pixel signals of pixel [4k, 4l+2] and pixel[4k+2, 4l+2].The store even activation signal ST_EVEN[4 k+2] is set to activate theeven row signal transfer switch SW5 to transfer and store the averaginglight conversion signal of the first pixel of the third row of physicalpixels of the lth row of the super-pixel on capacitor CE[4 k+2].

Simultaneously, the column averaging of the first and second green-1(G1) pixels of the super-pixel of the even row 4l+2 is accomplished bysetting the column averaging signal COL_AVE[4 k+1] to activate thecolumn averaging switch SW4 to connect the storage capacitor CS(i+1) inparallel with the storage capacitor CS(i+3) to average the first andsecond green-1 (G1) pixel signals of pixel [4k+1, 4l+2] and pixel[4k+3,4l+2]. The store even activation signal ST_EVEN[4 k+3] is set toactivate the even row signal transfer switch SW5 to transfer and storethe averaging light conversion signal of the second pixel of the thirdrow of the lth row of the super-pixel on capacitor CE[4 k+3].

The column averaging of the third and fourth red (R) pixels of the evenrow 4l+2 by setting the column averaging signal COL_AVE[4(k+1)] toactivate the column averaging switch SW4 to connect the storagecapacitor CS(i+4) in parallel with the storage capacitor CS(i+6) toaverage the third and fourth red (R) pixel signals of pixel [4(k+1),4l+2] and pixel[4(k+1)+2, 4l+2]. The store even activation signalST_EVEN[4(k+1)+2] is set to activate the even row signal transfer switchSW5 to transfer and store the averaging light conversion signal of thethird pixel of the third row of the lth row of the super-pixel oncapacitor CE[4(k+1)+2].

The column averaging of the third and fourth green-1 (G1) pixels of thesuper-pixel of the even row 4l+2 is accomplished by setting the columnaveraging signal COL_AVE[4(k+1)] to activate the column averaging switchSW4 to connect the storage capacitor CS(i+5) in parallel with thestorage capacitor CS(i+7) to average the first and second green-1 (G1)pixel signals of pixel [4(k+1)+1, 4l+2] and pixel[4(k+1)+3, 4l+2]. Thestore even activation signal ST_EVEN[4(k+1)+3] is set to activate theeven row signal transfer switch SW5 to transfer and store the averaginglight conversion signal of the second pixel of the lth row of thesuper-pixel on capacitor CE[4(k+1)+3].

The row addresses ROW_ADDR[N:0] are set to address the fourth physicalrow 4l+3 of the first super-pixel row l. The row select signal ROW_SEL,sample and hold signal SH, the clamp signal CLAMP, and the pixel resetsignal PIX_RST are activated as shown in FIG. 7 to convert the lightsignal to the differential light conversion electrical output signalVOUT(i) and transfer the differential light conversion electrical outputsignal VOUT(i) to the storage capacitor CS(i) for each column (i) of thephysical row 4l+3.

The averaging of the first and second green-2 (G2) pixels of the odd row4l+3 by setting the column averaging signal COL_AVE[4 k] to activate thecolumn averaging switch SW4 to connect the storage capacitor CS(i) inparallel with the storage capacitor CS(i+2) to average the first andsecond green-2 (G2) pixel signals of pixel [4k, 4l+3] and pixel[4k+2,4l+3]. The store odd activation signal ST_ODD[4 k+2] is set to activatethe odd row signal transfer switch SW5 to transfer and store theaveraging light conversion signal of the first pixel of the 4l+3 row ofthe lth row of the super-pixel on capacitor CO[4 k+2].

The column averaging of the first and second blue (B) pixels of thesuper-pixel of the odd row 4l+3 is accomplished by setting the columnaveraging signal COL_AVE[4 k+1] to activate the column averaging switchSW₄ to connect the storage capacitor CS(i+1) in parallel with thestorage capacitor CS(i+3) to average the first and second blue (B) pixelsignals of pixel [4k+1, 4l+3] and pixel[4k+3, 4l+3]. The store oddactivation signal ST_ODD[4 k+3] is set to activate the odd row signaltransfer switch SW₅ to transfer and store the averaging light conversionsignal of the second pixel of the l^(th) row of the super-pixel oncapacitor CO[4 k+3].

The column averaging of the third and fourth green-2 (G2) pixels of theodd row 4l+3 by setting the column averaging signal COL_AVE[4(k+1)] toactivate the column averaging switch SW₄ to connect the storagecapacitor CS(i+4) in parallel with the storage capacitor CS(i+6) toaverage the third and fourth green-2 (G2) pixel signals of pixel[4(k+1), 4l+3] and pixel[4(k+1)+2, 4l+3]. The store odd activationsignal ST_ODD[4(k+1)+2] is set to activate the odd row signal transferswitch SW₅ to transfer and store the averaging light conversion signalof the third pixel of the l^(th) row of the super-pixel on capacitorCO[4(k+1)+2].

The column averaging of the third and fourth blue (B) pixels of thesuper-pixel of the odd row 4l+3 is accomplished by setting the columnaveraging signal COL_AVE[4(k+1)+1] to activate the column averagingswitch SW₄ to connect the storage capacitor CS(i+5) in parallel with thestorage capacitor CS(i+7) to average the first and second green-1 (G1)pixel signals of pixel [4(k+1)+1, 4l+3] and pixel[4(k+1)+3, 4l+3]. Thestore odd activation signal ST_ODD[4(k+1)+3] is set to activate the oddrow signal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the second pixel of the l^(th) row of thesuper-pixel on capacitor CO[4(k+1)+3].

After the completion of the column averaging of the four physical rowsof 4l, 4l+1, 4l+2, and 4l+3 described above, the averaged pixelinformation in column direction has been stored in the capacitors CE(i)and CO(i). FIG. 11 shows the differential light conversion electricaloutput signals that are averaged and stored on each storage capacitorCE(i) and CO(i) in column SHCAC block. During the readout timeReadout(l) of the super-pixel row l, the stored differential lightconversion electrical output signals are row averaged or row binned andare readout to external circuitry such as an analog-to-digital converterthrough the video amplifier/switched capacitor integrator circuit 170 ofFIGS. 9 c-9 d. Details on readout the averaged column differential lightconversion electrical output signals to the column bus COL_BUS isdescribed hereinafter.

After read out the signals of l^(th) row of super-pixel, the storagecapacitors CE(i) and CO(i) are, as described in FIG. 6 b, reset by thereset pulse CECO_RST. Then, the operation on (l+1)^(th) row ofsuper-pixels starts and is identical to that described above for the(l)^(th) row of super-pixels. The (l+1)^(th) row of super-pixelsincludes the physical rows 4(l+1), 4(l+1)+1, 4(l+1)+2, and 4(l+1)+3 andthe physical columns 4k, 4k+1, 4k+2, 4k+3, 4(k+1), 4(k+1)+1, 4(k+1)+2,and 4(k+1)+3. The operation as described above stores the averageddifferential light conversion electrical output signals of each of thecolumns of the selected row on the storage capacitors CE(i) and CO(i).The column averaged differential light conversion electrical outputsignals are row averaged or row binned and are transferred during thereadout time Readout(l+1) to the external circuitry such as ananalog-to-digital converter for further processing.

The second example for a decimation ratio of 3:1 is shown in FIGS. 12 a,12 b, and 12 c. For the decimation ratio of 3:1, the column and rows ofeach super-pixel starts at the physical column and row addresses thatare a multiple of the decimation ratio. In a Bayer patterned array ofCMOS active pixel sensors, the evaluation to determine the magnitude ofthe colors of each of the super-pixels requires that twice thedecimation ratio (n) of physical rows and columns (2n=6, where n=3). Bysetting the column counter to i=6k in the section of column SHCAC blockshown in FIGS. 9 a-9 d, physical column i represents the start column ofthe super-pixel column. At this setting, columns 6k, 6k+1, 6k+2, 6k+3,6k+4, and 6k+5 cover the range of k^(th) super-pixel column in thecolumn direction of the array of CMOS active pixel sensors. Columns6(k+1)=6k+4, 6(k+1)+1, 6(k+1)+2, 6(k+1)+3, 6(k+1)+4, and 6(k+1)+5, coverthe range of (k+1)^(th) super-pixel column in the physical columndirection. FIGS. 12 a, 12 b, and 12 c provide the waveforms thatdemonstrate the analog signal process for the averaging of the physicalcolumns of the super-pixel columns the l^(th) and (l+1)^(th) super-pixelrow of the array of CMOS active pixel sensors. At the 3:1 imagedecimation ratio, the l^(th) row of super-pixel includes rows 6l, 6l+1,6l+2, 6l+3, 6l+4, and 6l+5, and the (l+1)^(th) row of super-pixelincludes rows 6(l+1)=6l+6, 6l+7, 6l+8, 6l+9, 6l+10, and 6l+11.

As described above, the column averaging operation is controlled by thecolumn averaging switches SW₄, even row signal transfer switch SW₅, andodd row signal transfer switch SW₆ in each column SHCAC circuit. Thecolumn averaging switches SW₄, even row signal transfer switch SW₅, andodd row signal transfer switch SW₆ are programmed ON/OFF depending onthe image decimation ratio (n). The waveforms in FIGS. 12 a, 12 b, and12 c show the activation signals for the column averaging switches SW₄,even row signal transfer switch SW₅, and odd row signal transfer switchSW₆. The row addresses ROW_ADDR[N:0] for the l^(th) row of a super-pixelby addressing the physical row 6l, 6l+1, 6l+2, 6l+3, 6l+4, and 6l+5which are row averaged or row binned and are then readout during thereadout period Readout(l).

At the beginning of the evaluation of the l^(th) row of the super-pixel,all the even and odd storage capacitors CE(i) and CO(i), are, asdescribed in FIG. 6 b, reset by the global reset signal CECO_RST. Thereset pulse CECO_RST is given after the readout period of theinformation of (l−1)^(th) super-pixel row. The row addressesROW_ADDR[N:0] are set to address the desired first physical row (6l) ofthe l^(th) row of the super-pixel. The row select signal ROW_SEL, thesample and hold signal SH, the clamp signal CLAMP, and the pixel resetsignal PIX_RST are activated as shown in FIG. 7 to convert the lightsignal to the differential light conversion electrical output signalV_(OUT)(i).

The averaging of the columns of the first super-pixel row l begins withthe column averaging of the first, second, and third red (R) pixels ofthe even row 6l by setting the column averaging signals COL_AVE[6 k] andCOL_AVE[6 k+2] to activate the column averaging switches SW₄ to connectthe storage capacitor CS(i) in parallel with the storage capacitorsCS(i+2) and CS(i+4) to average the first, second, and third red (R)pixel signals of pixel [6k, 6l], pixel[6k+2, 6l], and pixel[6k+4, 6l].The store even activation signal ST_EVEN[6 k] is set to activate theeven row signal transfer switch SW₅ to transfer and store the averagedlight conversion signal of the first pixel of the l^(th) row of thesuper-pixel on capacitor CE[6 k].

Simultaneously, the column averaging of the first, second, and thirdgreen-1 (G1) pixels of the super-pixel of the even row 6l isaccomplished by setting the column averaging signals COL_AVE[6 k+1] andCOL_AVE[6 k+3] to activate the column averaging switches SW₄ to connectthe storage capacitor CS(i+1) in parallel with the storage capacitorsCS(i+3) and CS(i+5) to average the first, second, and third green-1 (G1)pixel signals of pixel [6k+1, 6l], pixel[6k+3, 6l], and pixel[6k+5, 6l].The store even activation signal ST_EVEN[6 k+1] is set to activate theeven row signal transfer switch SW₅ to transfer and store the averagedlight conversion signal of the second pixel of the l^(th) row of thesuper-pixel on capacitor CE[6 k+1].

The column averaging of the fourth, fifth, and sixth red (R) pixels ofthe even row 6l by setting the column averaging signals COL_AVE[6(k+1)]and COL_AVE[6(k+1)+2] to activate the column averaging switch SW₄ toconnect the storage capacitor CS(i+6) in parallel with the storagecapacitors CS(i+8) and CS(i+10) to average the fourth, fifth, and sixthred (R) pixel signals of pixel [6(k+1), 6l] and pixel[6(k+1)+2, 6l]. Thestore even activation signal ST_EVEN[6(k+1)] is set to activate the evenrow signal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the third pixel of the l^(th) row of thesuper-pixel on capacitor CE[6(k+1)].

The column averaging of the fourth, fifth, and sixth green-1 (G1) pixelsof the super-pixel of the even row 6l is accomplished by setting thecolumn averaging signals COL_AVE[6(k+1)+1] and COL_AVE[6(k+1)+3] toactivate the column averaging switches SW₄ to connect the storagecapacitor CS(i+6) in parallel with the storage capacitor CS(i+8) andCS(i+10) to average the fourth, fifth, and sixth green-1 (G1) pixelsignals of pixel [6(k+1)+1, 6l] and pixel[6(k+1)+3, 6l]. The store evenactivation signal ST_EVEN[6(k+1)+1] is set to activate the even rowsignal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the second pixel of the l^(th) row of thesuper-pixel on capacitor CE[6(k+1)+1].

The row addresses ROW_ADDR[N:0] are set to address the second physicalrow (6l+1) of the l^(th) row of the super-pixel. The row select signalROW_SEL is activated to select the second physical row 6l+1 of the firstsuper-pixel row l. The sample and hold signal SH, the clamp signalCLAMP, and the pixel reset signal PIX_RST are activated as shown in FIG.7 to convert the light signal to the differential light conversionelectrical output signal V_(OUT)(i) and transfer the differential lightconversion electrical output signal V_(OUT)(i) to the storage capacitorCS(i) for each column (i).

The averaging of the first, second, and third green-2 (G2) pixels of theodd row 6l+1 by setting the column averaging signals COL_AVE[6 k] andCOL_AVE[6 k+2] to activate the column averaging switches SW₄ to connectthe storage capacitor CS(i) in parallel with the storage capacitorsCS(i+2) and CS(i+4) to average the first, second, and third green-2 (G2)pixel signals of pixel [6k, 6l+1], pixel[6k+2, 6l+1], and [6k+4, 6l+1].The store odd activation signal ST_ODD[6 k] is set to activate the oddrow signal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the first pixel of the l^(th) row of thesuper-pixel on capacitor CO[6 k].

The column averaging of the first, second, and third blue (B) pixels ofthe super-pixel of the odd row 6l+1 is accomplished by setting thecolumn averaging signals COL_AVE[6 k+1] and COL_AVE[6 k+3] to activatethe column averaging switch SW₄ to connect the storage capacitor CS(i+1)in parallel with the storage capacitors CS(i+3) and CS(i+5) to averagethe first, second, and third blue (B) pixel signals of pixel [6k+1,6l+1], pixel[6k+3, 6l+1], and pixel[6k+5, 6l+1]. The store oddactivation signal ST_ODD[6 k+1] is set to activate the odd row signaltransfer switch SW₅ to transfer and store the averaging light conversionsignal of the second pixel of the l^(th) row of the super-pixel oncapacitor CO[6 k+1].

The column averaging of the fourth, fifth, and sixth green-2 (G2) pixelsof the odd row 6l+1 by setting the column averaging signalsCOL_AVE[6(k+6)] and COL_AVE[6(k+8)] to activate the column averagingswitch SW₄ to connect the storage capacitor CS(i+6) in parallel with thestorage capacitors CS(i+8) and CS(i+10) to average the fourth, fifth,and sixth green-2 (G2) pixel signals of pixel [6(k+1), 6l+1],pixel[6(k+1)+2, 6l+1], and pixel[6(k+1)+4, 6l+1]. The store oddactivation signal ST_ODD[6(k+1)] is set to activate the odd row signaltransfer switch SW₅ to transfer and store the averaging light conversionsignal of the third pixel of the l^(th) row of the super-pixel oncapacitor CO[6(k+1)].

The column averaging of the fourth, fifth, and sixth blue (B) pixels ofthe super-pixel of the odd row 6l+1 is accomplished by setting thecolumn averaging signals COL_AVE[6(k+1)+1] and COL_AVE[6(k+1)+3] toactivate the column averaging switch SW₄ to connect the storagecapacitor CS(i+7) in parallel with the storage capacitors CS(i+9) andCS(i+11) to average the fourth, fifth, and sixth blue (B) pixel signalsof pixel [6(k+1)+1, 6l], pixel[6(k+1)+3, 6l], and pixel[6(k+1)+5, 6l].The store odd activation signal ST_ODD[6(k+1)+1] is set to activate theodd row signal transfer switch SW₅ to transfer and store the averaginglight conversion signal of the second pixel of the l^(th) row of thesuper-pixel on capacitor CO[6(k+1)+1].

The row addresses ROW_ADDR[N:0] are set to address the desired thirdphysical row (6l+2) of the l^(th) row of the super-pixel. The row selectsignal ROW_SEL, the sample and hold signal SH, the clamp signal CLAMP,and the pixel reset signal PIX_RST are activated as shown in FIG. 7 toconvert the light signal to the differential light conversion electricaloutput signal V_(OUT)(i).

The averaging of the columns of the third physical row 6l+2 of thesuper-pixel row l begins with the column averaging of the first, second,and third red (R) pixels of the even row 6l+2 by setting the columnaveraging signals COL_AVE[6 k] and COL_AVE[6 k+2] to activate the columnaveraging switches SW₄ to connect the storage capacitor CS(i) inparallel with the storage capacitors CS(i+2) and CS(i+4) to average thefirst, second, and third red (R) pixel signals of pixel [6k, 6l],pixel[6k+2, 6l+2], and pixel[6k+4, 6l+2]. The store even activationsignal ST_EVEN[6 k+2] is set to activate the even row signal transferswitch SW₅ to transfer and store the averaged light conversion signal ofthe first pixel of the l^(th) row of the super-pixel on capacitor CE[6k+2].

Simultaneously, the column averaging of the first, second, and thirdgreen-1 (G1) pixels of the super-pixel of the even row 6l+2 isaccomplished by setting the column averaging signals COL_AVE[6 k+1] andCOL_AVE[6 k+3] to activate the column averaging switches SW₄ to connectthe storage capacitor CS(i+1) in parallel with the storage capacitorsCS(i+3) and CS(i+5) to average the first, second, and third green-1 (G1)pixel signals of pixel [6k+1, 6l+2], pixel[6k+3, 6l+2], and pixel[6k+5,6l]. The store even activation signal ST_EVEN[6 k+3] is set to activatethe even row signal transfer switch SW₅ to transfer and store theaveraged light conversion signal of the second pixel of the l^(th) rowof the super-pixel on capacitor CE[6 k+3].

The column averaging of the fourth, fifth, and sixth red (R) pixels ofthe even row 6l+2 by setting the column averaging signalsCOL_AVE[6(k+1)] and COL_AVE[6(k+1)+2] to activate the column averagingswitch SW₄ to connect the storage capacitor CS(i+6) in parallel with thestorage capacitors CS(i+8) and CS(i+10) to average the fourth, fifth,and sixth red (R) pixel signals of pixel [6(k+1), 6l+2] andpixel[6(k+1)+2, 6l+2]. The store even activation signalST_EVEN[6(k+1)+2] is set to activate the even row signal transfer switchSW₅ to transfer and store the averaging light conversion signal of thethird pixel of the l^(th) row of the super-pixel on capacitorCE[6(k+1)+2].

The column averaging of the fourth, fifth, and sixth green-1 (G1) pixelsof the super-pixel of the even row 6l+2 is accomplished by setting thecolumn averaging signals COL_AVE[6(k+1)+1] and COL_AVE[6(k+1)+3] toactivate the column averaging switches SW₄ to connect the storagecapacitor CS(i+6) in parallel with the storage capacitor CS(i+8) andCS(i+10) to average the fourth, fifth, and sixth green-1 (G1) pixelsignals of pixel [6(k+1)+1, 6l+2] and pixel[6(k+1)+3, 6l+2]. The storeeven activation signal ST_EVEN[6(k+1)+3] is set to activate the even rowsignal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the second pixel of the l^(th) row of thesuper-pixel on capacitor CE[6(k+1)+3].

The row addresses ROW_ADDR[N:0] are set to address the fourth physicalrow (6l+3) of the l^(th) row of the super-pixel. The row select signalROW_SEL is activated to select the fourth physical row 6l+3 of the firstsuper-pixel row l. The sample and hold signal SH, the clamp signalCLAMP, and the pixel reset signal PIX_RST are activated as shown in FIG.7 to convert the light signal to the differential light conversionelectrical output signal V_(OUT)(I) and transfer the differential lightconversion electrical output signal V_(OUT)(I) to the storage capacitorCS(i) for each column (i).

The averaging of the first, second, and third green-2 (G2) pixels of theodd row 6l+3 by setting the column averaging signals COL_AVE[6 k] andCOL_AVE[6 k+2] to activate the column averaging switches SW₄ to connectthe storage capacitor CS(i) in parallel with the storage capacitorsCS(i+2) and CS(i+4) to average the first, second, and third green-2 (G2)pixel signals of pixel [6k, 6l+3], pixel[6k+2, 6l+3], and [6k+4, 6l+3].The store odd activation signal ST_ODD[6 k+2] is set to activate the oddrow signal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the first pixel of the l^(th) row of thesuper-pixel on capacitor CO[6 k+2].

The column averaging of the first, second, and third blue (B) pixels ofthe super-pixel of the odd row 6l+3 is accomplished by setting thecolumn averaging signals COL_AVE[6 k+1] and COL_AVE[6 k+3] to activatethe column averaging switch SW₄ to connect the storage capacitor CS(i+1)in parallel with the storage capacitors CS(i+3) and CS(i+5) to averagethe first, second, and third blue (B) pixel signals of pixel [6k+1,6l+3], pixel[6k+3, 6l+3], and pixel[6k+5, 6l+3]. The store oddactivation signal ST_ODD[6 k+3] is set to activate the odd row signaltransfer switch SW₅ to transfer and store the averaging light conversionsignal of the second pixel of the l^(th) row of the super-pixel oncapacitor CO[6 k+3].

The column averaging of the fourth, fifth, and sixth green-2 (G2) pixelsof the odd row 6l+3 by setting the column averaging signalsCOL_AVE[6(k+6)] and COL_AVE[6(k+8)] to activate the column averagingswitch SW₄ to connect the storage capacitor CS(i+6) in parallel with thestorage capacitors CS(i+8) and CS(i+10) to average the fourth, fifth,and sixth green-2 (G2) pixel signals of pixel [6(k+1), 6l+3],pixel[6(k+1)+2, 6l+3], and pixel[6(k+1)+4, 6l+3]. The store oddactivation signal ST_ODD[6(k+1)+2] is set to activate the odd row signaltransfer switch SW₅ to transfer and store the averaging light conversionsignal of the third pixel of the l^(th) row of the super-pixel oncapacitor CO[6(k+1)+2].

The column averaging of the fourth, fifth, and sixth blue (B) pixels ofthe super-pixel of the odd row 6l+3 is accomplished by setting thecolumn averaging signals COL_AVE[6(k+1)+1] and COL_AVE[6(k+1)+3] toactivate the column averaging switch SW₄ to connect the storagecapacitor CS(i+7) in parallel with the storage capacitors CS(i+9) andCS(i+11) to average the fourth, fifth, and sixth blue (B) pixel signalsof pixel [6(k+1)+1, 6l+3], pixel[6(k+1)+3, 6l+3], and pixel[6(k+1)+5,6l+3]. The store odd activation signal ST_ODD[6(k+1)+3] is set toactivate the odd row signal transfer switch SW₅ to transfer and storethe averaging light conversion signal of the second pixel of the l^(th)row of the super-pixel on capacitor CO[6(k+1)+3].

The row addresses ROW_ADDR[N:0] are set to address the desired fifthphysical row (6l+4) of the l^(th) row of the super-pixel. The row selectsignal ROW_SEL, the sample and hold signal SH, the clamp signal CLAMP,and the pixel reset signal PIX_RST are activated as shown in FIG. 7 toconvert the light signal to the differential light conversion electricaloutput signal V_(OUT)(i).

The averaging of the columns of the fifth physical row 6l+4 of thesuper-pixel row l begins with the column averaging of the first, second,and third red (R) pixels of the even row 6l+4 by setting the columnaveraging signals COL_AVE[6 k] and COL_AVE[6 k+2] to activate the columnaveraging switches SW₄ to connect the storage capacitor CS(i) inparallel with the storage capacitors CS(i+2) and CS(i+4) to average thefirst, second, and third red (R) pixel signals of pixel [6k, 6l+4],pixel[6k+2, 6l+4], and pixel[6k+4, 6l+4]. The store even activationsignal ST_EVEN[6 k+6] is set to activate the even row signal transferswitch SW₅ to transfer and store the averaged light conversion signal ofthe first pixel of the l^(th) row of the super-pixel on capacitor CE[6k+4].

Simultaneously, the column averaging of the first, second, and thirdgreen-1 (G1) pixels of the super-pixel of the even row 6l+4 isaccomplished by setting the column averaging signals COL_AVE[6 k+1] andCOL_AVE[6 k+3] to activate the column averaging switches SW₄ to connectthe storage capacitor CS(i+1) in parallel with the storage capacitorsCS(i+3) and CS(i+5) to average the first, second, and third green-1 (G1)pixel signals of pixel [6k+1, 6l+4], pixel[6k+3, 6l+4], and pixel[6k+5,6l+4]. The store even activation signal ST_EVEN[6 k+5] is set toactivate the even row signal transfer switch SW₅ to transfer and storethe averaged light conversion signal of the second pixel of the l^(th)row of the super-pixel on capacitor CE[6 k+5].

The column averaging of the fourth, fifth, and sixth red (R) pixels ofthe even row 6l+4 by setting the column averaging signalsCOL_AVE[6(k+1)] and COL_AVE[6(k+1)+2] to activate the column averagingswitch SW₄ to connect the storage capacitor CS(i+6) in parallel with thestorage capacitors CS(i+8) and CS(i+10) to average the fourth, fifth,and sixth red (R) pixel signals of pixel [6(k+1), 6l+4] andpixel[6(k+1)+2, 6l+4]. The store even activation signalST_EVEN[6(k+1)+4] is set to activate the even row signal transfer switchSW₅ to transfer and store the averaging light conversion signal of thethird pixel of the l^(th) row of the super-pixel on capacitorCE[6(k+1)+4].

The column averaging of the fourth, fifth, and sixth green-1 (G1) pixelsof the super-pixel of the even row 6l+4 is accomplished by setting thecolumn averaging signals COL_AVE[6(k+1)+1] and COL_AVE[6(k+1)+3] toactivate the column averaging switches SW₄ to connect the storagecapacitor CS(i+6) in parallel with the storage capacitor CS(i+8) andCS(i+10) to average the fourth, fifth, and sixth green-1 (G1) pixelsignals of pixel [6(k+1)+1, 6l+4] and pixel[6(k+1)+3, 6l+4]. The storeeven activation signal ST_EVEN[6(k+1)+5] is set to activate the even rowsignal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the second pixel of the l^(th) row of thesuper-pixel on capacitor CE[6(k+1)+5].

The row addresses ROW_ADDR[N:0] are set to address the sixth physicalrow (6l+5) of the l^(th) row of the super-pixel. The row select signalROW_SEL is activated to select the sixth physical row 6l+5 of the firstsuper-pixel row l. The sample and hold signal SH, the clamp signalCLAMP, and the pixel reset signal PIX_RST are activated as shown in FIG.7 to convert the light signal to the differential light conversionelectrical output signal V_(OUT)(i) and transfer the differential lightconversion electrical output signal V_(OUT)(i) to the storage capacitorCS(i) for each column (i).

The averaging of the first, second, and third green-2 (G2) pixels of theodd row 6l+5 by setting the column averaging signals COL_AVE[6 k] andCOL_AVE[6 k+2] to activate the column averaging switches SW₄ to connectthe storage capacitor CS(i) in parallel with the storage capacitorsCS(i+2) and CS(i+4) to average the first, second, and third green-2 (G2)pixel signals of pixel [6k, 6l+1], pixel[6k+2, 6l+1], and [6k+4, 6l+1].The store odd activation signal ST_ODD[6 k+4] is set to activate the oddrow signal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the first pixel of the l^(th) row of thesuper-pixel on capacitor CO[6 k+4].

The column averaging of the first, second, and third blue (B) pixels ofthe odd row 6l+5 is accomplished by setting the column averaging signalsCOL_AVE[6 k+1] and COL_AVE[6 k+3] to activate the column averagingswitch SW₄ to connect the storage capacitor CS(i+1) in parallel with thestorage capacitors CS(i+3) and CS(i+5) to average the first, second, andthird blue (B) pixel signals of pixel [6k+1, 6l+5], pixel[6k+3, 6l+5],and pixel[6k+5, 6l+5]. The store odd activation signal ST_ODD[6 k+5] isset to activate the odd row signal transfer switch SW₅ to transfer andstore the averaging light conversion signal of the second pixel of thel^(th) row of the super-pixel on capacitor CO[6 k+5].

The column averaging of the fourth, fifth, and sixth green-2 (G2) pixelsof the odd row 6l+5 by setting the column averaging signalsCOL_AVE[6(k+6)] and COL_AVE[6(k+8)] to activate the column averagingswitch SW₄ to connect the storage capacitor CS(i+6) in parallel with thestorage capacitors CS(i+8) and CS(i+10) to average the fourth, fifth,and sixth green-2 (G2) pixel signals of pixel [6(k+1), 6l+1],pixel[6(k+1)+2, 6l+1], and pixel[6(k+1)+4, 6l+1]. The store oddactivation signal ST_ODD[6(k+1)+4] is set to activate the odd row signaltransfer switch SW₅ to transfer and store the averaging light conversionsignal of the third pixel of the l^(th) row of the super-pixel oncapacitor CO[6(k+1)+4].

The column averaging of the fourth, fifth, and sixth blue (B) pixels ofthe super-pixel of the odd row 6l+5 is accomplished by setting thecolumn averaging signals COL_AVE[6(k+1)+1] and COL_AVE[6(k+1)+3] toactivate the column averaging switch SW₄ to connect the storagecapacitor CS(i+7) in parallel with the storage capacitors CS(i+9) andCS(i+11) to average the fourth, fifth, and sixth blue (B) pixel signalsof pixel [6(k+1)+1, 6l+5], pixel[6(k+1)+3, 6l+5], and pixel[6(k+1)+5,6l+5]. The store odd activation signal ST_ODD[6(k+1)+5] is set toactivate the odd row signal transfer switch SW₅ to transfer and storethe averaging light conversion signal of the second pixel of the l^(th)row of the super-pixel on capacitor CO[6(k+1)+5].

After the completion of the column averaging of the six physical rows of6l, 6l+1, 6l+2, 6l+3, 6l+4, and 6l+5 described above, the averaged pixelinformation in column direction has been stored in the capacitors CE(i)and CO(i). FIG. 13 shows the differential light conversion electricaloutput signals that are averaged and stored on each storage capacitorCE(i) and CO(i) in column SHCAC block. During the readout timeReadout(l) of the super-pixel row l, the stored differential lightconversion electrical output signals are row averaged or row binned andare readout to external circuitry such as an analog-to-digital converterthrough the video amplifier/switched capacitor integrator circuit 170 ofFIG. 9 d. Details on readout the averaged column differential lightconversion electrical output signals to the column bus COL_BUS isdescribed hereinafter.

After read out the signals of l^(th) row of super-pixel, the storagecapacitors CE(i) and CO(i) are, as described in FIG. 6 b, reset by thereset pulse CECO_RST. Then, the operation on (l+1)^(th) row ofsuper-pixels starts and is identical to that described above for the(l)^(th) row of super-pixels. The (l+1)^(th) row of super-pixelsincludes the physical rows 6(l+1), 6(l+1)+1, 6(l+1)+2, 6(l+1)+3,6(l+1)+4, and 6(l+1)+5, and the physical columns 6k, 6k+1, 6k+2, 6k+3,6k+4, 6k+5, 6(k+1), 6(k+1)+1, 6(k+1)+2, 6(k+1)+3, 6(k+1)+5, and6(k+1)+5. The operation as described above stores the averageddifferential light conversion electrical output signals of each of thecolumns of the selected row on the storage capacitors CE(i) and CO(i).The averaged differential light conversion electrical output signals arerow averaged or row binned and are transferred during the readout timeReadout(l+1) to the external circuitry such as an analog-to-digitalconverter for further processing.

For the general case where the decimation ratio of n:1, the column androws of each super-pixel starts at the physical column and row addressesthat are a multiple of the decimation ratio. As noted above, in a Bayerpatterned array of CMOS active pixel sensors, the evaluation todetermine the magnitude of the colors of each of the super-pixelsrequires that twice the decimation ratio (n) of physical rows andcolumns (2n). By setting the column counter to i=2nk in the section ofcolumn SHCAC block shown in FIGS. 9 a-9 d, physical column i representsthe start column of the super-pixel column. At this setting, columns2nk, 2nk+1, 2nk+2, . . . , 2n(k+1)−2, and 2n(k+1)−1 cover the range ofk^(th) super-pixel column in the column direction of the array of CMOSactive pixel sensors. Columns 2n(k+1), 2n(k+1)+1, 2n(k+1)+2, . . . ,2n(k+2)−2, and 2n(k+2)−1 cover the range of (k+1)^(th) super-pixelcolumn in the physical column direction. FIGS. 14 a-14 c provide thewaveforms that demonstrate the analog signal process for the averagingof the physical columns of the super-pixel columns of the l^(th) and(l+1)^(th) super-pixel row of the array of CMOS active pixel sensors. Atthe n:1 image decimation ratio, the l^(th) row of super-pixel includesrows 2nl, 2nl+1, . . . , 2n(l+1)−2, and 2n(l+1)−1 and the (l+1)^(th) rowof super-pixel includes rows 2n(l+1), 2n(l+1)+1, . . . , 2n(l+2)−2, and2n(l+2)−1.

As described above, the column averaging operation is controlled by thecolumn averaging switches SW₄, even row signal transfer switch SW₅, andodd row signal transfer switch SW₆ in each column SHCAC circuit. Thecolumn averaging switches SW₄, even row signal transfer switch SW₅, andodd row signal transfer switch SW₆ are programmed ON/OFF depending onthe image decimation ratio (n). The waveforms in FIGS. 14 a-14 c showthe activation signals for the column averaging switches SW₄, even rowsignal transfer switch SW₅, and odd row signal transfer switch SW₆. Therow addresses ROW_ADDR[N:0] for the l^(th) row of a super-pixel byaddressing the physical row 2n2nl, 2nl+1, . . . , 2n(l+1)−2, and2n(l+1)−1 which are then are row averaged or row binned and are readoutduring the readout period Readout(l).

At the beginning of the evaluation of the l^(th) row of the super-pixel,all the even and odd storage capacitors CE(i) and CO(i) are, asdescribed in FIG. 6 b, reset by the global reset signal CECO_RST. Thereset pulse CECO_RST is given after the readout period of theinformation of (l−1)^(th) super-pixel row. The row addressesROW_ADDR[N:0] are set to address the desired physical row of the l^(th)row of the super-pixel. The row select signal ROW_SEL, the sample andhold signal SH, the clamp signal CLAMP, and the pixel reset signalPIX_RST are activated as shown in FIG. 7 to convert the light signal tothe differential light conversion electrical output signal V_(OUT)(i).

The averaging of the columns of the first super-pixel row l begins withthe column averaging of the first n red (R) pixels of the even row 2nlby setting the column averaging signals COL_AVE[2 nk+(2 i)]|_(i=0)^(n−1) to activate the column averaging switches SW₄ to connect thestorage capacitors CS[2 nk+(2 i)]|_(i=0) ^(n−1) in parallel to averagethe first n red (R) pixel signals of pixels [2nk+(2i)]|_(i=0) ^(n−1).The store even activation signal ST_EVEN[2 nk] is set to activate theeven row signal transfer switch SW₅ to transfer and store the averaginglight conversion signal of the first pixel of the l^(th) row of thesuper-pixel on capacitor CE[2 nk].

Simultaneously, the column averaging of the first n green-1 (G1) pixelsof the super-pixel of the even row 2nl is accomplished by setting thecolumn averaging signals COL_AVE[2 nk+(2 i+1)]|_(i=0) ^(n−1) to activatethe column averaging switches SW₄ to connect the storage capacitor CS[2nk+(2 i+1)]|_(i=0) ^(n−1) in parallel to average the first n green-1(G1) pixel signals of pixels [2nk+(2i)]|_(i=0) ^(n−1). The store evenactivation signal ST_EVEN[2 nk+1] is set to activate the even row signaltransfer switch SW₅ to transfer and store the averaging light conversionsignal of the second pixel of the l^(th) row of the super-pixel oncapacitor CE[2 nk+1].

In a similar fashion, the column averaging of the remaining groups of nred (R) pixels of the even row 2nl is accomplished by setting the columnaveraging signals COL_AVE[2nk + (2i)]❘_(i = 0)^(n − 1)❘_(k = 0)^(N − 1),where N is the number of super-pixels in the horizontal direction of theactive pixel sensor $\left( {N = \frac{TOT\_ HorzPixels}{n}} \right)$to activate the column averaging switches SW₄ to connect the storagecapacitors CS[2nk + (2i)]❘_(i = 0)^(n − 1)❘_(k = 0)^(N − 1)in parallel to average each of the groups of n red (R) pixel signals ofpixels [2nk + (2i)]❘_(i = 0)^(n − 1)❘_(k = 0)^(N − 1).The store even activation signalST_EVEN[[2nk + (2i)]|_(i = 0)^(n − 1)|_(k = 0)^(N − 1)]is set to activate each of the respective even row signal transferswitches SW₅ to transfer and store the averaging light conversion signalof the third pixel of the l^(th) row of the super-pixel on capacitorCE[2nk + (2i)]|_(i = 0)^(n − 1)|_(k = 0)^(N − 1).

In a similar fashion, the column averaging of the remaining groups of ngreen-1 (G) pixels of the even row 2nl is accomplished by setting thecolumn averaging signalsCOL_AVE[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)to activate the column averaging switches SW₄ to connect the storagecapacitors CS[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)in parallel to average each of the groups of n green-1 (G) pixel signalsof pixels [2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1).The store even activation signalST_EVEN[[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)]is set to activate each of the respective even row signal transferswitches SW₅ to transfer and store the averaging light conversion signalof the third pixel of the l^(th) row of the super-pixel on capacitorCE[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1).

The row select signal ROW_SEL is activated to select the second physicalrow 2nl+1 of the first super-pixel row l. The sample and hold signal SH,the clamp signal CLAMP, and the pixel reset signal PIX_RST are activatedas shown in FIG. 7 to convert the light signal to the differential lightconversion electrical output signal V_(OUT)(i) and transfer thedifferential light conversion electrical output signal V_(OUT)(i) to thestorage capacitor CS(i) for each column (i).

The averaging of the first n green-2 (G2) pixels of the odd row 2nl+1 bysetting the column averaging signals COL_AVE[2 n k+(2 i)]|_(i=0) ^(N−1)to activate the column averaging switches SW₄ to connect the storagecapacitors CS[2 nk+(2 i)]|_(i=0) ^(N−1) in parallel to average the firstn green-2 (G2) pixel signals of pixels [2nk+(2i)]|_(i=0) ^(N−1). Thestore odd activation signal ST_ODD[2 nk] is set to activate the odd rowsignal transfer switch SW₅ to transfer and store the averaging lightconversion signal of the first pixel of the l^(th) row of thesuper-pixel on capacitor CO[2 nk].

The column averaging of the first n blue (B) pixels of the super-pixelof the odd row 2nl+1 is accomplished by setting the column averagingsignals COL_AVE[2 n(k+1)+(2 i)]|_(i=0) ^(N−1) to activate the columnaveraging switches SW₄ to connect the storage capacitor CS[2 n(k+1)+(2i)]_(i=0) ^(N−1) in parallel with the storage capacitor CS[2 n(k+1)+(2i)]|_(i=0) ^(N−1) to average the first n (B) pixel signals of pixels[2n(k+1)+(2i)]|_(i=0) ^(N−1). The store odd activation signal ST_ODD[2nk+1] is set to activate the odd row signal transfer switch SW₅ totransfer and store the averaging light conversion signal of the secondpixel of the l^(th) row of the super-pixel on capacitor CO[2 nk+1].

In a similar fashion, the column averaging of the remaining groups of ngreen-2 (G2) pixels of the odd row 2nl+1 is accomplished by setting thecolumn averaging signalsCOL_AVE[2nk + (2i)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)to activate the column averaging switches SW₄ to connect the storagecapacitors CS[2nk + (2i)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)in parallel to average each of the groups of n green-2 (G2) pixelsignals of pixels [2nk + (2i)]_(i = 0)^(n − 1)_(k = 0)^(N − 1).The store odd activation signalST_ODD[[2nk + (2i)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)]is set to activate each of the respective even row signal transferswitches SW₅ to transfer and store the averaging light conversion signalof the 2n+k|_(k=0) ^(N−1) pixel of the l^(th) row of the super-pixel oncapacitor CO[2nk + (2i)]_(i = 0)^(n − 1)_(k = 0)^(N − 1).

In a similar fashion, the column averaging of the remaining groups of nblue (B) pixels of the super-pixel of the odd row 2nl+1 is accomplishedby setting the column averaging signalsCOL_AVE[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)to activate the column averaging switches SW₄ to connect the storagecapacitors CS[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)in parallel to average each of the groups of n blue (B) pixel signals ofpixels [2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1).The store even activation signalST_ODD[[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)]is set to activate each of the respective even row signal transferswitches SW₅ to transfer and store the averaging light conversion signalof the 2n+(k+1)|_(k=0) ^(N−1) pixel of the l^(th) row of the super-pixelon capacitor CO[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(n − 1).

The even and odd storage capacitorsCE[2nk + (2i)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)and CO[2nk + (2i)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)store the differential light conversion electrical output signal V_(OUT)for the averaged columns of the first and second rows of the l^(th) rowof super-pixels. Likewise, as shown in the following, the even and oddstorage capacitors CE(i+2) and CO(i+2), CE(i+3) and CO(i+3), CE(i+6) andCO(i+6), CE(i+7) and CO(i+7) store the differential light conversionelectrical output signals V_(OUT) for the averaged columns of the thirdand fourth rows of the l^(th) row of super-pixels.

As described above, the row addresses ROW_ADDR[N:0] are iteratively setto address the remaining even physical rows 2nl+2j|_(j=1) ^(n−1) of thel^(th) row of the super-pixel. At each iteration, the row select signalROW_SEL, the sample and hold signal SH, the clamp signal CLAMP, and thepixel reset signal PIX_RST are activated as shown in FIG. 7 to convertthe light signal to the differential light conversion electrical outputsignal V_(OUT)(i) for each of the columns.

The averaging of the columns of the row of pixels 2nl+2j|_(j−1) ^(n−1)column averages each group of n red (R) pixels of the even row2nl+2j|_(j=1) ^(n−1) by setting the column averaging signalCOL_AVE[2n(k + m) + (2i)]_(i = 0)^(n − 2)_(m = 0)^(n − 2)to activate the column averaging switches SW₄ to connect the storagecapacitors CS(i) CS[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)in parallel average each group of n red (R) pixel signals of pixels[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1), 2nl + 2j_(j = 1)^(n − 1)].Upon the averaging of each group, the store even activation signalST_EVEN[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)for that group is set to activate the even row signal transfer switchesSW₅ to transfer and store the averaging light conversion signal of thefirst pixel of the each row of physical pixels of the l^(th) row of thesuper-pixel on the capacitorsCE[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1).

Simultaneously, The averaging of the columns of the row of pixels2nl+2j|_(j=1) ^(n−1) column averages each group of n green-1 (G1) pixelsof the even row 2nl+2j|_(j=1) ^(n−1) by setting the column averagingsignal COL_AVE[2n(k + m) + (2i + 1)]_(i = 0)^(n − 2)_(m = 0)^(n − 2)to activate the column averaging switches SW₄ to connect the storagecapacitorsCS(i)CS[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)in parallel average each group of n green-1 (G1) pixel signals of pixels[[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)❘_(m = 0)^(n − 1), 2nl + 2j_(j = 1)^(n − 1)].Upon the averaging of each group, the store even activation signalST_EVEN[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)for that group is set to activate the even row signal transfer switchesSW₅ to transfer and store the averaging light conversion signal of thefirst pixel of the each row of physical pixels of the l^(th) row of thesuper-pixel on the capacitorsCE[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)_(m = 0)^(n − 1).

Additionally, as described above, the row addresses ROW_ADDR[N:0] areiteratively set to address the remaining odd physical rows2nl+(2j+1)|_(j=1) ^(n−1) of the l^(th) row of the super-pixel. At eachiteration, the row select signal ROW_SEL, the sample and hold signal SH,the clamp signal CLAMP, and the pixel reset signal PIX_RST are activatedas shown in FIG. 7 to convert the light signal to the differential lightconversion electrical output signal V_(OUT)(i) for each of the columns.

The averaging of the columns of the odd rows of pixels 2nl+(2j+1)|_(j=1)^(n−1) column averages each group of n green-2 (G2) pixels of the oddrow 2nl+(2j+1)|_(j=1) ^(n−1) by setting the column averaging signalCOL_AVE[2n(k + m) + (2i + 1)]_(i = 0)^(n − 2)_(m = 0)^(n − 2)to activate the column averaging switches SW₄ to connect the storagecapacitorsCS(i)CS[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)in parallel average each group of n green-2 (G2) pixel signals of pixels[[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)_(m = 0)^(n − 1), 2nl + 2j❘_(j = 1)^(n − 1)].Upon the averaging of each group, the store odd activation signalST_ODD[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)for that group is set to activate the odd row signal transfer switchesSW₅ to transfer and store the averaging light conversion signal of thefirst pixel of the each row of physical pixels of the l^(th) row of thesuper-pixel on the capacitorsCO[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1).

Simultaneously, the averaging of the columns of the odd rows of pixels2nl+(2j+1)|_(j=1) ^(n−1) column averages each group of n blue (B) pixelsof the odd row 2nl+(2j+1)|_(j=1) ^(n−1) by setting the column averagingsignal COL_AVE[2n(k + m) + (2i + 1)]_(i = 0)^(n − 2)_(m = 0)^(n − 2)to activate the column averaging switches SW₄ to connect the storagecapacitorsCS(i)CS[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)in parallel average each group of n blue (B) pixel signals of pixels[[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)_(m = 0)^(n − 1), 2nl + 2j❘_(j = 1)^(n − 1)].Upon the averaging of each group, the store odd activation signalST_ODD[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)or that group is set to activate the odd row signal transfer switchesSW₅ to transfer and store the averaging light conversion signal of thefirst pixel of the each row of physical pixels of the l^(th) row of thesuper-pixel on the capacitorsCO[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1).

After the completion of the column averaging of the n physical rows2nl+(2j)|_(j=0) ^(n−1) and 2nl+(2j+1)|_(j=0) ^(n−1) described above, theaveraged pixel information in column direction has been stored in thecapacitors CO[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)and CE[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1).FIG. 15 shows the differential light conversion electrical outputsignals that are averaged and stored on each storage capacitorCO[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)and CE[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)in column SHCAC block. During the readout time Readout(l) of thesuper-pixel row l, the stored differential light conversion electricaloutput signals are row averaged or row binned and are readout toexternal circuitry such as an analog-to-digital converter through thevideo amplifier/switched capacitor integrator circuit 170 of FIGS. 9 c-9d. Details on readout the averaged column differential light conversionelectrical output signals to the column bus COL_BUS is describedhereinafter.

After read out the signals of l^(th) row of super-pixel, the storagecapacitorsCO[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)  and  CE[2nk + (2i + 1)]_(i = 0)^(n − 1)_(k = 0)^(N − 1)are, as described in FIG. 6 b, reset by the reset pulse CECO_RST. Then,the operation on (l+1)^(th) row of super-pixels starts and is identicalto that described above for the (l)^(th) row of super-pixels. The(l+1)^(th) row of super-pixels includes the physical rows2nl+(2j)|_(j=0) ^(n−1) and 2nl+(2j+1)|_(j=0) ^(n−1) and the physicalcolumns[2n(k + m)(2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)  and  [[2n(k + m) + (2i + 1)]_(i = 0)^(n − 1)❘_(m = 0)^(n − 1), 2nl + 2j_(j = 0)^(n − 1)].The operation as described above stores the averaged differential lightconversion electrical output signals of each of the columns of theselected row on the storage capacitorsCE[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1)  and  CO[2n(k + m) + (2i)]_(i = 0)^(n − 1)_(m = 0)^(n − 1).The averaged differential light conversion electrical output signals arerow averaged or row binned and are transferred during the readout timeReadout(l+1) to the external circuitry such as an analog-to-digitalconverter for further processing.

The remaining rows (l+2), . . . , (l+x), where x is the number ofsuper-pixel rows of the array of CMOS active pixel sensors, areevaluated iteratively in pairs of rows as described above. The columnaverage for each physical row being available on each of the storagecapacitors for readout. Depending upon the light intensity, the physicalrows may be averaged within a super-pixel row in high intensity lightoperation or may be integrated for binning in low intensity operation.The decision to operate the SHCAC of FIG. 9 a-9 d between row averagingand row binning is made by an algorithm implemented in the address,timing, and control processor circuit 165 of FIG. 5 based on theaveraging signal level. The row averaging and row binning is explainedbelow.

At high light levels, the output voltage of single bright pixel signalis high enough to meet the full signal swing. However, for decimatedimage with low resolution (used as viewfinder or video stream), it isstill desired to have high spatial resolution. Pixel averaging readoutoperation is used in this condition.

The row averaging circuit 135 of FIGS. 6 and 8 consists of the rowaveraging selection switches Sw₉ and SW₁₀ that are respectivelycontrolled by the terminals RAVE_EVEN and RAVE_ODD. In each column, asshown in FIGS. 9 a-9 d, the row averaging circuit connects the storagecapacitors CE(i) and CO(i) to the storage capacitors CE(i+1) and CO(i+1)of the same color adjacent column averaging circuits. Thus, when the rowaveraging selection switches Sw₉ and SW₁₀ are activated the physicalrows of each super-pixel are connected to average the magnitude of thecolumn averaged differential light conversion electrical output signalsfor the super-pixel to enhance image spatial resolution only.

Referring to FIGS. 16 a-16 c, the even row averaging switches Sw₉ areactivated by the even row activation signals RAVE_EVEN[N:0;i.ne.{(2mn).or.(2 mn+1)}]|_(m=0) ^(N−1) to connect the storage capacitors CE(i)of the physicals rows of each row of the super-pixels together toaverage the column averaged pixels of each physical row of thesuper-pixels. The even row activation signals RAVE_EVEN[N:0;i.eq.{(2mn).or.(2 mn+1)}]_(m=0) ^(N−1) are not activated to segregate thephysical rows of adjacent super-pixels from each other.

The column address decoder 140 decodes the column addresses 145 of FIG.5 and sets the even column select signalsCSEL_EVEN[2n(k + m) + (r)]_(r = 0)¹_(m = 0)^(n − 1)sequentially activates the first two switches SW₅ of each super-pixel totransfer the red (R) and green-1 (G1) row averaged signals of the to thevideo amplifier/switched capacitor integrator circuit 170 for transferto the external circuitry.

At the completion of the transfer of the even row red (R) and green-1(G1) averaged signals, the row averaging switches SW₁₀ are activated bythe odd row activation signals RAVE_ODD[N:0;i.ne.{(2 mn).or.(2mn+1)}]|_(m=0) ^(N−1) to connect the storage capacitors CO(i) of thephysicals rows of each row of the super-pixels together to average thecolumn averaged pixels of each physical row of the super-pixels. The oddrow activation signals RAVE_ODD[N:0;i.eq.{(2 mn).or.(2 mn+1)}]|_(m=0)^(N−1) are not activated to segregate the physical rows of adjacentsuper-pixels from each other.

The column address decoder 140 decodes the column addresses 145 of FIG.5 and sets the odd column select signalsCSEL_ODD[2n(k + m) + (r)]_(r = 0)¹_(m = 0)^(n − 1)sequentially activates the first two switches SW₅ of each super-pixel totransfer the row averaged signals of the green-2 (G2) and blue (B) tothe video amplifier/switched capacitor integrator circuit 170 fortransfer to the external circuitry.

Refer back to FIG. 6 c for the discussion of the structure and operationof the video amplifier/switched capacitance integration circuit 170 ofthis invention. As described above, the analog gain G of the videoamplifier/switched capacitor integrator circuit 170 is the ratio of thesampling capacitor CSMPL to the feedback capacitor CFB (CSMPL/CFB). Thefirst sampling switch control signal SMPL1, second sampling controlswitch SMPL2, and reset control pulse RST_CFB are activated during eachperiod that the column address 145 has selected a column address of theactive pixel sensor to provide a switched capacitor amplification of thecolumn output signal V_(COL) to generate the analog output signalV_(OUT).

In the high light level conditions, the effective output voltage of theanalog signal 175 at the output of the video amplifier/switchedcapacitor integration circuit 170 for each of the column averaged androw averaged pixels is given by the equations:${{R{^\circ}}\left( {k,l} \right)} = {\frac{1}{n \times n}*G*\left( \frac{n*{CS}}{{n*{CS}} + {CST}} \right){\sum\limits_{i = 0}^{n - 1}\quad{\sum\limits_{j = 0}^{n - 1}\quad\left\lbrack {R\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}$${{G1{^\circ}}\left( {k,l} \right)} = {\frac{1}{n \times n}*G*\left( \frac{n*{CS}}{{n*{CS}} + {CST}} \right){\sum\limits_{i = 0}^{n - 1}\quad{\sum\limits_{j - 0}^{n - 1}\quad\left\lbrack {{G1}\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}$${{G2{^\circ}}\left( {k,l} \right)} = {\frac{1}{n \times n}*G*\left( \frac{n*{CS}}{{n*{CS}} + {CST}} \right){\sum\limits_{i = 0}^{n - 1}\quad{\sum\limits_{j = 0}^{n - 1}\quad\left\lbrack {{G2}\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}$${{B{^\circ}}\left( {k,l} \right)} = {\frac{1}{n \times n}*G*\left( \frac{n*{CS}}{{n*{CS}} + {CST}} \right){\sum\limits_{i = 0}^{n - 1}\quad{\sum\limits_{j = 0}^{n - 1}\quad\left\lbrack {B\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}$

where:

-   -   n is the decimation ratio of the sub-sampling of the array.    -   CS is the effective value of the sample and hold capacitor        CS(i).    -   CST is the value of the storage capacitor CE(i) or CE(i)    -   G is the gain of the video amplifier/switched capacitor        integrator circuit 170.    -   i is the counting variable for the neighboring pixels in a row        dimension of the sub sampled array 15.    -   j is the counting variable for the neighboring pixels for a        column dimension of the sub sampled array 15.    -   k is the counting variable for a row dimension of the sub        sampled array 15.    -   l is the counting variable for the column dimension of the sub        sampled array 15.    -   R^(O) is the red pixel of the sub sampled array 15.    -   G1^(O) is the first green pixel of the sub sampled array 15.    -   G2^(O) is the second green pixel of the sub sampled array 15.    -   B^(O) is the blue pixel of the sub sampled array 15.

At low light levels, although the row averaging of the column averagedpixels provides the high spatial resolution need for the low resolutionsuch as the viewfinder or video stream, the overall signal level is lowthat makes the signal-to-noise ratio (SNR) very low. To achieve the highspatial resolution and high SNR, all the even rows of the columnaveraged pixels of each super-pixel are integrated or added together andall the odd rows of the column averaged pixels of each super-pixel areintegrated or added together to provide a row binning of the pixels thevideo amplifier/switched capacitance integration circuit 170 of FIGS. 5,6 a, 6 c, and 8.

FIGS. 17 a-17 b illustrate the timing of the even and odd column selectsignals that activate the switches SW₇ and SW₈ necessary to perform thebinning integration in the video amplifier/switched capacitanceintegration circuit 170 of FIGS. 9 a-9 d. Referring to FIG. 5, thecolumn address decoder 140 receives the column address 145. The columnaddresses 140, as shown in FIGS. 17 a-17 b, are sequentially activatedto select each same color even and odd storage capacitor CE(i) and CO(i)for each super-pixel. The column address decoder 140 sequentiallyactivates the even column select linesCSEL_EVEN[2n(k + m) + (r)]_(r = 0)^(n − 1)_(m = 0)^(n − 1).The switches SW₇ are activated to connect the storage capacitorsCE[2n(k + m) + (r)]_(r = 0)¹_(m = 0)^(n − 1)to transfer the column averaged the column averaged differential lightconversion electrical output signals to the video amplifier/switchedcapacitor integrator 170. The video amplifier/switched capacitanceintegration circuit 170 integrated each of the column averageddifferential light conversion electrical output signals for eachphysical row of a super-pixel to create a row binned differential lightconversion electrical output signal of the analog output signal 175 thatis transferred to external circuit such as an analog-to-digitalconverter for further processing. The even column select linesCSEL_EVEN[2n(k + m) + (r)]_(r = 0)^(n − 1)_(m = 0)^(n − 1)are activated to generate the differential light conversion electricalsignals for the red (R) and green-1 (G1) super-pixels.

Upon completion of the odd row of the super-pixel, The column addressdecoder 140 sequentially activates the odd column select linesCSEL_ODD[2n(k + m) + (r)]❘_(r = 0)^(n − 1)❘_(m = 0)^(n − 1).The switches SW₅ are activated to connect the storage capacitorsCO[2n(k + m) + (r)]❘_(r = 0)¹❘_(m = 0)^(n − 1)to transfer the column averaged the column averaged differential lightconversion electrical output signals to the video amplifier/switchedcapacitor integrator 170.

Refer back to FIG. 6 c for the discussion of the structure and operationof the video amplifier/switched capacitance integration circuit 170 ofthis invention. The first sampling switch control signal SMPL1, secondsampling control switch SMPL2, and reset control pulse RST_CFB areactivated during each period that the column address 145 has selected acolumn address of the active pixel sensor to provide a switchedcapacitor amplification of the column output signal V_(COL) to generatethe analog output signal V_(OUT). For vertical pixel binning readout,the feedback capacitor has been reset at the beginning of n samplesreadout. In this case, the charge transfer from CSAML to CFB of the nreadout [e.g. column 2nk to 2n(k+1)−2] has been binned (added) at CFB.The output signal V_(OUT) of the video amplifier/switched capacitorintegrator circuit 170 is given by the equation:$V_{OUT} = {V_{CM} - {\frac{CSMPL}{CFB} \cdot {\sum\limits_{i = 0}^{n - 1}{V\quad{{A_{IN}\left( {{2{nk}} + {2i}} \right)}.}}}}}$

The video amplifier/switched capacitance integration circuit 170integrates each of the column averaged differential light conversionelectrical output signals for each physical row of a super-pixel tocreate a row binned differential light conversion electrical outputsignal of the analog output signal 175 that is transferred to externalcircuit such as an analog-to-digital converter for further processing.The odd column select linesCSEL_ODD[2n(k + m) + (r)]❘_(r = 0)^(n − 1)❘_(m = 0)^(n − 1)are activated to generate the differential light conversion electricalsignals for the green-2 (G2) and blue (B) super-pixels.

As noted above, the even and odd row averaging activation signalsRAVE_EVEN[N:0] and RAVE_ODD[N:0] are not activated. The videoamplifier/switched integration circuit 170 provides the binning functionfor providing sufficient spatial resolution and better SNR at low lightlevel not achievable by the row averaging circuit 135 of FIGS. 5, 6, and8.

In the low light level conditions, the effective output voltage of theanalog signal 175 at the output of the video amplifier/switchedcapacitor integration circuit 170 for each of the column averaged androw binned pixels is given by the equations:${R^{O}\left( {k,l} \right)} = {\frac{1}{n}*G*\left( \frac{n*{CS}}{{n*{CS}} + {CST}} \right){\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {R\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}$${G\quad 1^{O}\left( {k,l} \right)} = {\frac{1}{n}*G*\left( \frac{n*{CS}}{{n*{CS}} + {CST}} \right){\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j - 0}^{n - 1}\left\lbrack {G\quad 1\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}$${G\quad 2^{O}\left( {k,l} \right)} = {\frac{1}{n}*G*\left( \frac{n*{CS}}{{n*{CS}} + {CST}} \right){\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {G\quad 2\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}$${B^{O}\left( {k,l} \right)} = {\frac{1}{n}*G*\left( \frac{n*{CS}}{{n*{CS}} + {CST}} \right){\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {B\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}$

where:

-   -   n is the decimation ratio of the sub-sampling of the array.    -   CS is the effective value of the sample and hold capacitor        CS(i).    -   CST is the value of the storage capacitor CE(i) or CE(i)    -   G is the gain of the video amplifier/switched capacitor        integrator circuit 170. The analog gain G of the video        amplifier/switched capacitor integrator circuit 170 is the ratio        of the sampling capacitor CSMPL to the feedback capacitor CFB        (CSMPL/CFB).    -   i is the counting variable for the neighboring pixels in a row        dimension of the sub sampled array 15.    -   j is the counting variable for the neighboring pixels for a        column dimension of the sub sampled array 15.    -   k is the counting variable for a row dimension of the sub        sampled array 15.    -   l is the counting variable for the column dimension of the sub        sampled array 15.    -   R^(O) is the red pixel of the sub sampled array 15.    -   G1^(O) is the first green pixel of the sub sampled array 15.    -   G2^(O) is the second green pixel of the sub sampled array 15.    -   B^(O) is the blue pixel of the sub sampled array 15.

When the CMOS active pixel array is to function at full resolution, therow addresses 110 of FIG. 5 are set to sequentially address each row ofthe CMOS active pixel array. Each pixel is reset and the lightconversion is initiated. The sample and hold circuit 125 of FIGS. 5, 6,and 8 captures the light conversion electrical signal V_(out) and thelight conversion electrical signal through the source follower SF₁ foreach column of the addressed row. The light conversion electrical signalis then selectively transferred through the column select switch SW₃ tothe column bus 180 to the video amplifier/switched capacitor integrator170. In this operation the switched capacitor integrator is inoperativeand the video signal is amplified and transferred as the analog signalto external circuitry Refer now to FIG. 18 the column select signalsCOL_SEL[0], . . . , COL_SEL[i], . . . , COL_SEL[N] are sequentiallyactivated to set the switches SW₃ to transfer the light conversionelectrical signals V_(OUT) to the video amplifier/switched capacitorintegrator circuit 170 of FIG. 9 d as the analog signal 175 to externalcircuitry (analog-to-digital converter) for further processing. Each rowis sequentially selected and the column selection as described isrepeated for each row.

FIG. 19 illustrates a second embodiment of the sample and hold columnaveraging circuit of this invention. The SHCAC circuit is essentiallyidentical to the structure and function of the first embodiment of FIG.6 a, except the source followers SF of FIG. 6 a are eliminated thuscreating a passive column averaging, row averaging/binning circuit ofthis invention. The SHCAC circuit with the source followers SFeliminated has very low column fixed pattern noise. Alternately, theelimination of the source followers SF causes the signal dilution fromthe charge sharing between effective sampling capacitor CS and the largeparasitic capacitor CP of the column bus COL_BUS. The output voltageV_(COL) at the column bus COL_BUS is determined by the equation:$V_{COL} = {\frac{\left( \frac{{CS}\quad{1 \cdot {CS}}\quad 2}{{{CS}\quad 1} + {{CS}\quad 2}} \right)}{\left( \frac{{CS}\quad{1 \cdot {CS}}\quad 2}{{{CS}\quad 1} + {{CS}\quad 2}} \right) + {CP}} \cdot V_{OUT}}$

Where:

-   -   V_(COL) is the voltage level representing the light level        impinging upon the pixel being sensed.    -   CS1 is the capacitance value of the series capacitor CS1.    -   CS2 is the capacitance value of the series capacitor CS2.    -   CP is the capacitance value of the parasitic capacitor CP.

For large arrays of CMOS active pixel sensors, the large parasiticcapacitance CP of the column bus COL_BUS (due to long routed wiring anda large number of switches) is the main contributor to the dilution ofthe output voltage VCOL to the video amplifier/switched capacitorintegrator 170.

For resolution adjustment of the array of CMOS active pixel sensors, theimage decimation by using column averaging, row averaging/binningapproach can also be implemented into the passive column readout andwill reduce the signal dilution effect since a high column outputvoltage VOUT is expected.

FIGS. 20 a-20 d, in composite, form the schematic of passive columnSHCAC of this invention. The reset switches for the storage capacitorsCE and CO are not illustrated and are as shown in FIG. 6 b. As describedabove, the reset switches are controlled by the global control switchreset signal CECO_RST.

The operation of the passive SHCAC is identical to that described abovefor the first embodiment incorporating the source followers SF. In orderto get highest effective gain, for the passive SHCAC, the capacitance ofstorage capacitor CE(i) or CE(i) is optimized. Based on the theoreticalanalysis, the optimized size of the storage capacitor CE(i) or CE(i) isthe square root of the product of effective sampling capacitor CS(i) andline parasitic capacitor CP.

The input voltage V_(COL) at the input of the video amplifier/switchedcapacitor integrator 170 in full resolution image readout for each ofthe output pixels R^(O), G1^(O), G2^(O), and B^(O) is given by:${R^{O}\left( {i,j} \right)} = {{\frac{CS}{{CS} + {CP}}*{R\left( {i,j} \right)}} = {\frac{1}{1 + \alpha}{R\left( {i,j} \right)}}}$${G\quad 1^{O}\left( {i,j} \right)} = {{\frac{CS}{{CS} + {CP}}*G\quad 1\left( {i,j} \right)} = {\frac{1}{1 + \alpha}G\quad 1\left( {i,j} \right)}}$${G\quad 2^{O}\left( {i,j} \right)} = {{\frac{CS}{{CS} + {CP}}*G\quad 2\left( {i,j} \right)} = {\frac{1}{1 + \alpha}G\quad 2\left( {i,j} \right)}}$${B^{O}\left( {i,j} \right)} = {{\frac{CS}{{CS} + {CP}}*{B\left( {i,j} \right)}} = {\frac{1}{1 + \alpha}{B\left( {i,j} \right)}}}$

where:

-   -   n is the decimation ratio of the sub-sampling of the array.    -   i is the counting variable for the neighboring pixels in a row        dimension of the sub sampled array 15.    -   j is the counting variable for the neighboring pixels for a        column dimension of the sub sampled array 15.    -   α is the ratio of the parasitic capacitance CP to the effective        capacitance value CS of the sample and hold capacitances C1 and        C2.    -   R^(O) is the red pixel of the sub sampled array 15.    -   G1^(O) is the first green pixel of the sub sampled array 15.    -   G2^(O) is the second green pixel of the sub sampled array 15.    -   B^(O) is the blue pixel of the sub sampled array 15.

The capacitance value of the storage capacitor CE(i) or CE(i) isassigned according to the equation:CST=√{square root over (CS*CP)}

where:

-   -   CST is the value of the storage capacitor CE(i) or CE(i)        The values of the input voltage V_(COL) at the input of the        video amplifier/switched capacitor integrator 170 for each of        the output pixels R^(O), G1^(O), G2^(O), and B^(O) in a column        and row averaging operation is given by:        ${R^{O}\left( {k,l} \right)} = {\frac{1}{\left( {1 + \frac{\sqrt{\alpha}}{n}} \right)^{2}}{\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {R\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}$        ${G\quad 1^{O}\left( {k,l} \right)} = {\frac{1}{\left( {1 + \frac{\sqrt{\alpha}}{n}} \right)^{2}}{\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j - 0}^{n - 1}\left\lbrack {G\quad 1\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j}}} \right)} \right\rbrack}}}$        ${G\quad 2^{O}\left( {k,l} \right)} = {\frac{1}{\left( {1 + \frac{\sqrt{\alpha}}{n}} \right)^{2}}{\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {G\quad 2\left( {{{2 \times n \times k} + {2 \times i}},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}$        ${B^{O}\left( {k,l} \right)} = {\frac{1}{\left( {1 + \frac{\sqrt{\alpha}}{n}} \right)^{2}}{\sum\limits_{i = 0}^{n - 1}{\sum\limits_{j = 0}^{n - 1}\left\lbrack {B\left( {{{2 \times n \times k} + {2 \times i} + 1},{{2 \times n \times l} + {2 \times j} + 1}} \right)} \right\rbrack}}}$

where:

-   -   n is the decimation ratio of the sub-sampling of the array.    -   α is the ratio of the parasitic capacitance CP to the effective        capacitance value CS of the sample and hold capacitances C1 and        C2.    -   i is the counting variable for the neighboring pixels in a row        dimension of the sub sampled array 15.    -   j is the counting variable for the neighboring pixels for a        column dimension of the sub sampled array 15.    -   k is the counting variable for a row dimension of the sub        sampled array 15.    -   l is the counting variable for the column dimension of the sub        sampled array 15.    -   R^(O) is the red pixel of the sub sampled array 15.    -   G1^(O) is the first green pixel of the sub sampled array 15.    -   G2^(O) is the second green pixel of the sub sampled array 15.    -   B^(O) is the blue pixel of the sub sampled array 15.        As can be seen, by comparing the full resolution result with the        averaged result of a super-pixel, the resultant input voltage        V_(COL) has been enhanced because of less voltage dilution.

The vertical pixel binning readout of passive SHCAC, is as describedabove for the active SHCAC. The output signal V_(OUT) of the videoamplifier/switched capacitor integrator circuit 170 is given by theequation:$V_{OUT} = {V_{CM} - {\frac{CSMPL}{CFB} \cdot {\sum\limits_{l = 0}^{n - 1}{V\quad{{A_{IN}\left( {{2{nk}} + {2i}} \right)}.}}}}}$The amplifier input voltage VA_(IN) being essentially the input voltageV_(COL) at the input of the video amplifier/switched capacitorintegrator 170.

While the above embodiments refers to an array of CMOS active pixelswith resolution adjustment circuitry having the primary color (Red,Green, and Blue) detectors arranged in a Bayer Pattern, it is in keepingwith the intent of this invention that other sensor arrays and arraypatterns may be employed. The structure of the column averaging processconnects columns having the same sense attributes for the sensing. Therow averaging likewise connects the same sense attributes of adjacentrows for averaging the same sense attributes for sensing. Similarly, therow binning will integrate the rows of the same sense attributes for thebinning process. For instance, the CMOS active pixels sensors may havethe four channel subtractive colors of Cyan, Magenta, Yellow, and Black.It is envisioned that the basic primary colors and the subtractiveprimary colors maybe combined on a single CMOS active pixel sensor arrayfor improved color purity. The resolution adjustment would requirecolumn averaging and row averaging or binning of same color adjacentcolors within a super-pixel. The structure of the sample and holdcircuitry, the column averaging circuitry, the row averaging circuitry,and the video amplifier/switched capacitor integration circuitry wouldbe identical. The main difference is the connectivity of the controlswitching and the timing and control of the switching to perform thecolumn averaging and row averaging or row binning.

While this invention has been particularly shown and described withreference to the preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade without departing from the spirit and scope of the invention.

1. A sensor resolution adjustment apparatus in communication with an array of sensors, wherein said array of sensors is organized in arrangements having a first dimension and a second dimension and has a plurality of sensor types arranged in a pattern to detect a phenomena and convert said phenomena to a conversion electrical signal, whereby each sensor type detects unique attributes of said phenomena, said sensor resolution adjustment apparatus adjusting sensor resolution for reception of the phenomena and comprising: a sensor array decimation circuit in communication with said array of sensors to partition said array of sensors into a plurality of sub-groups of said array of sensors and generate partition control signals identifying addresses of said sub-groups; a first dimensional averaging circuit in communication with said array of sensors to receive said conversion electrical signals and in communication with said sensor array decimation circuit to receive said partition control signals, from said partition control signals averaging said conversion electrical signals from sensors detecting common attributes from the first dimension of each of said plurality of said sub-groups of said array of sensors to generate first dimensional averaged electrical signals of said first dimension of said plurality of said sub-group of said array of sensors; and a second dimensional averaging circuit in communication with said first dimensional averaging circuit to receive said first dimensional averaged electrical signals of each sub-group of sensors that detect said common attributes arranged on said first dimension within each sub-group of the array of sensors, and in communication with said sensor array decimation circuit to receive said partition control signals and from said partition control signals to integrate said first dimensional averaged electrical signals for sensors having said common attributes on a second dimension of each of said plurality of said sub-groups of said array of sensors to selectively generate second dimensional averaged electrical signals of said second dimension of said plurality of said sub-group of sensors having common attributes of said array of sensors.
 2. The sensor resolution adjustment apparatus of claim 1 further comprising: an addressing, timing, and control processor circuit in communication with the sensor array decimation circuit, the first dimensional averaging circuit and the second dimensional averaging circuit to generate addressing, timing, control, and select signals to coordinate generation of the conversion electrical signals from the plurality of sub-groups of the array of sensors, averaging of the conversion electrical signals from selected sensors within said sub-group to generate the first dimensional averaged electrical signals and averaging of the first dimensional averaged electrical signals selectively generate the second dimensional averaged electrical signals.
 3. The sensor resolution adjustment apparatus of claim 2 further comprising a sample and hold circuit connected to the array of sensors to sample and hold the conversion electrical signals from selected sensors for transfer to said averaging circuit and in communication with said timing and control circuit to receive said timing, control, and select signals for sampling and holding said conversion electrical signals
 4. The sensor resolution adjustment apparatus of claim 2 wherein the second dimensional averaging circuit comprises: a plurality of second dimensional averaging switches, each second dimensional averaging switch connected to the first dimensional averaging circuit to receive first dimensional averaged electrical signals for sensors with said common attributes on the second dimension of each of said plurality of sub-groups of said array of sensors to average the first dimensional averaged electrical signals to create the second dimensional averaged electrical signals, each of said plurality of second dimensional averaging switches in communication with said addressing, timing, and control processor circuit to receive said addressing, timing, control, and select signals to selectively connect said first dimensional averaging circuits of sensors having said common attributes on the second dimension of each of said plurality of sub-groups of said array of sensors for said averaging.
 5. The sensor resolution adjustment apparatus of claim 2 wherein the first dimensional averaging circuit comprises: a first plurality of averaging capacitors, each averaging capacitor connected to receive the conversion electrical signal from the sensors of an associated sensor of the array of sensors on the first dimension; and a first plurality of averaging switches connected to receive the electrical signal from an adjacent sensor on said first dimension to selectively transfer said electrical signal from said adjacent sensor to a first selected averaging capacitor to average the electrical signals from an attached sensor and the adjacent sensors, each of said first plurality of averaging switches in communication with said timing and control circuit to receive said timing, control, and select signals to selectively connect one said averaging capacitors to average the conversion electrical signals of said associated sensors of the array of sensors on the first dimension.
 6. The sensor resolution adjustment apparatus of claim 4 wherein the first dimensional averaging circuit further comprises: a second plurality of averaging capacitors, each averaging capacitor connected to receive the conversion electrical signal from the sensors of an associated sensor of the array of sensors on the first dimension; and a second plurality of averaging switches connected to receive the conversion electrical signals from an adjacent sensor on said second dimension to selectively transfer said electrical signal from said adjacent sensor to a selected second averaging capacitor to average the electrical signals from an attached sensor and the adjacent sensors, each of said second plurality of averaging switches in communication with said timing and control circuit to receive said timing, control, and select signals to selectively connect said second averaging capacitors to average the conversion electrical signals of said associated sensors of the array of sensors on the second dimension.
 7. The sensor resolution adjustment apparatus of claim 1 of wherein the first dimension of the array of sensors is a column of said sensors and the second dimension of the array of sensors is a row of said sensors.
 8. The sensor resolution adjustment apparatus of claim 1 wherein said sensors are active pixels sensors, said phenomena is light impinging upon said array of sensors converts said light to the conversion electrical signal, and said pattern is a Bayer pattern.
 9. The sensor resolution adjustment apparatus of claim 1 further comprising an amplifier connected to selectively receive one of a group of electrical signals consisting of the conversion electrical signals, the second dimensional averaging electrical signals, and the second dimensional binned electrical signals to amplify and condition said selected electrical signals for external processing.
 10. The sensor resolution adjustment apparatus of claim 1 further comprising: a plurality of source follower circuits, each source follower connected to receive one of said conversion electrical signals, said first dimensional averaged electrical signals, and said second dimensional averaged electrical signals to isolate said received one of said conversion electrical signals, said first dimensional averaged electrical signals, and said second dimensional averaged electrical signals from effects of a parasitic capacitor present at an output bus of said sensor resolution adjustment circuit.
 11. A photo-sensor image resolution adjustment apparatus in communication with an array of image photo-sensors, wherein said array of image photo-sensors is organized in columns and rows and has a plurality of sensor types arranged in a pattern to detect light and convert said light to a light conversion electrical signal, whereby each sensor type detects unique colors of said light, said photo-sensor image resolution adjustment apparatus adjusting sensor resolution for reception of the light and comprising: a photo-sensor array decimation circuit in communication with said array of image photo-sensors to partition said array of image photo-sensors into a plurality of sub-groups of said array of image photo-sensors and generate partition control signals identifying addresses of said sub-groups; a column averaging circuit in communication with said array of image photo-sensors to receive said light conversion electrical signals and in communication with said photo-sensor array decimation circuit to receive said partition control signals, from said partition control signals averaging said light conversion electrical signals from photo-sensors detecting common colors from the columns of each of said plurality of said sub-groups of said array of image photo-sensors to generate column averaged electrical signals of said columns of said plurality of said sub-group of said array of image photo-sensors; and a row averaging circuit: in communication with said column averaging circuit to receive said column averaged electrical signals of each sub-group of photo-sensors that detect said common colors arranged on said columns within each sub-group of the array of image photo-sensors, and in communication with said photo-sensor array decimation circuit to receive said partition control signals and from said partition control signals to average said column averaged electrical signals for sensors having said common colors on rows of each of said plurality of said sub-groups of said array of image photo-sensors to create row averaged electrical signals of said rows of said plurality of said sub-group of photo-sensors having common colors of said array of image photo-sensors, and in communication with said timing and control circuit to receive said timing, control, and select signals for creating said row averaged electrical signals.
 12. The photo-sensor image resolution adjustment apparatus of claim 11 further comprising: an addressing, timing, and control processor circuit in communication with the photo-sensor array decimation circuit, the column averaging circuit, and the row binning circuit, and the row averaging circuit to provide addressing, timing, control, and select signals to coordinate generation of the light conversion electrical signals from the plurality of sub-groups of the array of image photo-sensors, averaging of the light conversion electrical signals from selected sensors within said sub-group to generate the column averaged electrical signals and selectively averaging of the column averaged electrical signals selectively generate the row averaged electrical signals.
 13. The photo-sensor image resolution adjustment apparatus of claim 12 wherein, if said averaging light intensity signals indicates a high intensity light environment, said addressing, timing, and control processor circuit selects said row averaging circuit for generating said row averaging electrical signals.
 14. The photo-sensor image resolution adjustment apparatus of claim 12 further comprising a sample and hold circuit connected to the array of image photo-sensors to sample and hold the light conversion electrical signals from selected photo-sensors for transfer to said column averaging circuit and in communication with said timing and control circuit to receive said timing, control, and select signals for sampling and holding said light conversion electrical signals.
 15. The photo-sensor image resolution adjustment apparatus of claim 12 wherein the row averaging circuit comprises: a plurality of row averaging switches, each row averaging switch connected to the column averaging circuit to receive column averaged electrical signals for sensors with said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors to average the column averaged light conversion electrical signals to create the row averaged electrical signals, each of said plurality of row averaging switches in communication with said addressing, timing, and control processor circuit to receive said addressing, timing, control, and select signals to selectively connect said column averaging circuits of sensors having said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors for said averaging.
 16. The photo-sensor image resolution adjustment apparatus of claim 12 wherein the column averaging circuit comprises: a first plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having a common color of the array of image photo-sensors on the columns; and a first plurality of averaging switches connected to receive the electrical signal from an adjacent photo-sensor on said columns to selectively transfer said electrical signal from said adjacent photo-sensor to a first selected averaging capacitor to average the conversion electrical signals from an attached photo-sensor and the adjacent photo-sensors, each of said first plurality of averaging switches in communication with said timing and control circuit to receive said timing, control, and select signals to selectively connect one said averaging capacitors to average the light conversion electrical signals of said associated photo-sensors of the array of image photo-sensors on the columns.
 17. The photo-sensor image resolution adjustment apparatus of claim 25 wherein the column averaging circuit further comprises: a second plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having the common color of the array of image photo-sensors on the columns; and a second plurality of averaging switches connected to receive the light conversion electrical signals from the adjacent photo-sensor on said rows to selectively transfer said electrical signal from said adjacent photo-sensor to a selected second averaging capacitor to average the electrical signals from an attached sensor and the adjacent photo-sensors, each of said second plurality of averaging switches in communication with said timing and control circuit to receive said timing, control, and select signals to selectively connect said second averaging capacitors to average the light conversion electrical signals of said associated sensors of the array of image photo-sensors on the rows.
 18. The photo-sensor image resolution adjustment apparatus of claim 11 wherein said photo-sensors are active pixels sensors and said light is impinging upon said array of active pixel sensors to convert the light to the light conversion electrical signal.
 19. The photo-sensor image resolution adjustment apparatus of claim 11 further comprising an amplifier connected to selectively receive one of a group of electrical signals consisting of the light conversion electrical signals, the row averaging electrical signals, and the row binning electrical signals to amplify and condition said selected electrical signals for external processing.
 20. The photo-sensor image resolution adjustment apparatus of claim 11 further comprising: a plurality of source follower circuits, each source follower connected to receive one of said light conversion electrical signals, said column averaged electrical signals, and said row averaged electrical signals to isolate said light conversion electrical signals, said column averaged electrical signals, and said row averaged electrical signals from effects of a parasitic capacitor present at an output bus of said photo-sensor image resolution adjustment circuit.
 21. An image photo-sensing device comprising: an array of image photo-sensors organized in columns and rows and having a plurality of sensor types arranged in a pattern to detect light and convert said light to a light conversion electrical signal, whereby each sensor type detects unique colors of said light; and a photo-sensor image resolution adjustment apparatus in communication with the array of image photo-sensors for adjusting sensor resolution for reception of the light of said array of photo-sensors, said photo-sensor image resolution adjustment apparatus comprising: a photo-sensor array decimation circuit in communication with said array of image photo-sensors to partition said array of image photo-sensors into a plurality of sub-groups of said array of image photo-sensors and generate partition control signals identifying addresses of said sub-groups, a column averaging circuit in communication with said array of image photo-sensors to receive said light conversion electrical signals and in communication with said photo-sensor array decimation circuit to receive said partition control signals, from said partition control signals averaging said light conversion electrical signals from photo-sensors detecting common colors from the columns of each of said plurality of said sub-groups of said array of image photo-sensors to generate column averaged electrical signals of said columns of said plurality of said sub-group of said array of image photo-sensors, and a row averaging circuit: in communication with said column averaging circuit to receive said column averaged electrical signals of each sub-group of photo-sensors that detect said common colors arranged on said columns within each sub-group of the array of image photo-sensors, and in communication with said photo-sensor array decimation circuit to receive said partition control signals and from said partition control signals to average said column averaged electrical signals for sensors having said common colors on rows of each of said plurality of said sub-groups of said array of image photo-sensors to create row averaged electrical signals of said rows of said plurality of said sub-group of photo-sensors having common colors of said array of image photo-sensors, and in communication with said timing and control circuit to receive said timing, control, and select signals for creating said row averaged electrical signals.
 22. The image photo-sensing device of claim 21 wherein the photo-sensor image resolution adjustment apparatus further comprises: an addressing, timing, and control processor circuit in communication with the photo-sensor array decimation circuit, the column averaging circuit, the row binning circuit, and the row averaging circuit to provide addressing, timing, control, and select signals to coordinate generation of the light conversion electrical signals from the plurality of sub-groups of the array of image photo-sensors, averaging of the light conversion electrical signals from selected sensors within said sub-group to generate the column averaged electrical signals, selectively binning of the column averaged electrical signals from selected photo-sensors within said sub-group to generate the row binning electrical signals, selectively averaging of the column averaged electrical signals selectively generate the row averaged electrical signals.
 23. The image photo-sensing device of claim 22 wherein the photo-sensor image resolution adjustment apparatus further comprises a sample and hold circuit connected to the array of image photo-sensors to sample and hold the light conversion electrical signals from selected photo-sensors for transfer to said averaging circuit and in communication with said timing and control circuit to receive said timing, control, and select signals for sampling and holding said light conversion electrical signals
 24. The image photo-sensing device of claim 22 wherein the row averaging circuit comprises: a plurality of row averaging switches, each row averaging switch connected to the column averaging circuit to receive column averaged electrical signals for sensors with said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors to average the column averaged light conversion electrical signals to create the row averaged electrical signals, each of said plurality of row averaging switches in communication with said timing and control circuit to receive said timing, control, and select signals to selectively connect said column averaging circuits of sensors having said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors for said averaging.
 25. The image photo-sensing device of claim 22 wherein the column averaging circuit comprises: a first plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having a common color of the array of image photo-sensors on the columns; and a first plurality of averaging switches connected to receive the electrical signal from an adjacent photo-sensor on said columns to selectively transfer said electrical signal from said adjacent photo-sensor to a first selected averaging capacitor to average the conversion electrical signals from an attached photo-sensor and the adjacent photo-sensors, each of said first plurality of averaging switches in communication with said timing and control circuit to receive said timing, control, and select signals to selectively connect one said averaging capacitors to average the light conversion electrical signals of said associated photo-sensors of the array of image photo-sensors on the columns.
 26. The image photo-sensing device of claim 25 wherein the column averaging circuit further comprises: a second plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having the common color of the array of image photo-sensors on the columns; and a second plurality of averaging switches connected to receive the light conversion electrical signals from the adjacent photo-sensor on said rows to selectively transfer said electrical signal from said adjacent photo-sensor to a selected second averaging capacitor to average the electrical signals from an attached sensor and the adjacent photo-sensors, each of said second plurality of averaging switches in communication with said timing and control circuit to receive said timing, control, and select signals to selectively connect said second averaging capacitors to average the light conversion electrical signals of said associated sensors of the array of image photo-sensors on the rows.
 27. The image photo-sensing device of claim 21 wherein said photo-sensors are active pixels sensors, said light is impinging upon said array of active pixel sensors to convert the light to the light conversion electrical signal, and said pattern is a Bayer pattern.
 28. The image photo-sensing device of claim 21 wherein the photo-sensor image resolution adjustment apparatus further comprises an amplifier connected to selectively receive one of a group of electrical signals consisting of the light conversion electrical signals and the row averaging electrical signals to amplify and condition said selected electrical signals for external processing.
 29. A method for photo-sensor image resolution adjustment comprising the steps of: providing an array of image photo-sensors, wherein said array of image photo-sensors is organized in columns and rows and has a plurality of sensor types arranged in a pattern to detect light and convert said light to a light conversion electrical signal, whereby each sensor type detects unique colors of said light; communicating with said array of image photo-sensors to partition said array of image photo-sensors into a plurality of sub-groups of said array of image photo-sensors and provide partition control signals; column averaging said light conversion electrical signals from photo-sensors detecting common colors from the columns of each of said plurality of said sub-groups of said array of image photo-sensors from said partition control signals to create column averaged electrical signals of said columns of said plurality of said sub-group of said array of image photo-sensors; and row averaging said column averaged electrical signals of each sub-group of photo-sensors that detect said common colors arranged on said columns within each sub-group of the array of image photo-sensors from said partition control signals
 30. The method for photo-sensor image resolution adjustment of claim 29 further comprising the steps of: providing addressing, timing, control, and select signals to coordinate generation of the light conversion electrical signals from the plurality of sub-groups of the array of image photo-sensors, averaging of the light conversion electrical signals from selected sensors within said sub-group to generate the column averaged electrical signals and provide select signals to activate the step of selectively averaging of the column averaged electrical signals selectively generate the row averaged electrical signals.
 31. The method for photo-sensor image resolution adjustment of claim 29 further comprising the steps of: sampling and holding the light conversion electrical signals from selected photo-sensors for averaging; and providing timing, control, and select signals for sampling and holding said light conversion electrical signals.
 32. The method for photo-sensor image resolution adjustment of claim 29 wherein said row averaging is accomplished by a row averaging circuit comprising: a plurality of row averaging switches, each row averaging switch connected to the column averaging circuit to receive column averaged electrical signals for sensors with said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors to average the column averaged light conversion electrical signals to create the row averaged electrical signals, each of said plurality of row averaging switches to receive said addressing, timing, control, and select signals to selectively connect said column averaging circuits of sensors having said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors for said averaging.
 33. The method for photo-sensor image resolution adjustment of claim 31 wherein column averaging is accomplished by a column averaging circuit comprising: a first plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having a common color of the array of image photo-sensors on the columns; and a first plurality of averaging switches connected to receive the electrical signal from an adjacent photo-sensor on said columns to selectively transfer said electrical signal from said adjacent photo-sensor to a first selected averaging capacitor to average the conversion electrical signals from an attached photo-sensor and the adjacent photo-sensors, each of said first plurality of averaging receive said timing, control, and select signals to electively connect one said averaging capacitors to average the light conversion electrical signals of said associated photo-sensors of the array of image photo-sensors on the columns.
 34. The method for photo-sensor image resolution adjustment of claim 33 wherein the column averaging circuit further comprises: a second plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having the common color of the array of image photo-sensors on the columns; and a second plurality of averaging switches connected to receive the light conversion electrical signals from the adjacent photo-sensor on said rows to selectively transfer said electrical signal from said adjacent photo-sensor to a selected second averaging capacitor to average the electrical signals from an attached sensor and the adjacent photo-sensors, each of said second plurality of averaging switches receive said timing, control, and select signals to selectively connect said second averaging capacitors to average the light conversion electrical signals of said associated sensors of the array of image photo-sensors on the rows.
 35. The method for photo-sensor image resolution adjustment of claim 29 wherein said photo-sensors are active pixels sensors and said light is impinging upon said array of active pixel sensors to convert the light to the light conversion electrical signal.
 36. The method for photo-sensor image resolution adjustment of claim 29 further comprising the step of selectively amplifying and conditioning one of a group of electrical signals consisting of the light conversion electrical signals and the row averaging electrical signals for external processing.
 37. The method for photo-sensor image resolution adjustment of claim 29 further comprising the steps of: isolating said light conversion electrical signals, said column averaged electrical signals, and said row averaged electrical signals from effects of a parasitic capacitor.
 38. A method for adjusting photo-sensor image resolution comprising the steps of: providing an array of image photo-sensors, wherein said array of image photo-sensors is organized in columns and rows and has a plurality of sensor types arranged in a pattern to detect light and convert said light to a light conversion electrical signal, whereby each sensor type detects unique colors of said light; communicating with said array of image photo-sensors to partition said array of image photo-sensors into a plurality of sub-groups of said array of image photo-sensors and provide partition control signals; column averaging said light conversion electrical signals from photo-sensors detecting common colors from the columns of each of said plurality of said sub-groups of said array of image photo-sensors from said partition control signals to create column averaged electrical signals of said columns of said plurality of said sub-group of said array of image photo-sensors; and row averaging said column averaged electrical signals of each sub-group of photo-sensors that detect said common colors arranged on said columns within each sub-group of the array of image photo-sensors from said partition control signals
 39. The method for photo-sensor image resolution adjustment of claim 38 further comprising the steps of: providing addressing, timing, control, and select signals to coordinate generation of the light conversion electrical signals from the plurality of sub-groups of the array of image photo-sensors, averaging of the light conversion electrical signals from selected sensors within said sub-group to generate the column averaged electrical signals and provide select signals to activate the step of selectively averaging of the column averaged electrical signals selectively generate the row averaged electrical signals.
 40. The method for photo-sensor image resolution adjustment of claim 38 further comprising the steps of: sampling and holding the light conversion electrical signals from selected photo-sensors for averaging; and providing timing, control, and select signals for sampling and holding said light conversion electrical signals.
 41. The method for photo-sensor image resolution adjustment of claim 38 wherein said row averaging comprises a row averaging circuit, said row averaging circuit including: a plurality of row averaging switches, each row averaging switch connected to the column averaging circuit to receive column averaged electrical signals for sensors with said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors to average the column averaged light conversion electrical signals to create the row averaged electrical signals, each of said plurality of row averaging switches to receive said addressing, timing, control, and select signals to selectively connect said column averaging circuits of sensors having said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors for said averaging.
 42. The method for photo-sensor image resolution adjustment of claim 40 wherein column averaging comprises a column averaging circuit, said column averaging circuit includes: a first plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having a common color of the array of image photo-sensors on the columns; and a first plurality of averaging switches connected to receive the electrical signal from an adjacent photo-sensor on said columns to selectively transfer said electrical signal from said adjacent photo-sensor to a first selected averaging capacitor to average the conversion electrical signals from an attached photo-sensor and the adjacent photo-sensors, each of said first plurality of averaging receive said timing, control, and select signals to electively connect one said averaging capacitors to average the light conversion electrical signals of said associated photo-sensors of the array of image photo-sensors on the columns.
 43. The method for photo-sensor image resolution adjustment of claim 33 wherein the column averaging circuit further comprises: a second plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having the common color of the array of image photo-sensors on the columns; and a second plurality of averaging switches connected to receive the light conversion electrical signals from the adjacent photo-sensor on said rows to selectively transfer said electrical signal from said adjacent photo-sensor to a selected second averaging capacitor to average the electrical signals from an attached sensor and the adjacent photo-sensors, each of said second plurality of averaging switches receive said timing, control, and select signals to selectively connect said second averaging capacitors to average the light conversion electrical signals of said associated sensors of the array of image photo-sensors on the rows.
 44. The method for photo-sensor image resolution adjustment of claim 38 wherein said photo-sensors are active pixels sensors and said light is impinging upon said array of active pixel sensors to convert the light to the light conversion electrical signal.
 45. The method for photo-sensor image resolution adjustment of claim 38 further comprising the step of selectively amplifying and conditioning one of a group of electrical signals consisting of the light conversion electrical signals and the row averaging electrical signals for external processing.
 46. The method for photo-sensor image resolution adjustment of claim 38 further comprising the steps of: isolating said light conversion electrical signals, said column averaged electrical signals, and said row averaged electrical signals from effects of a parasitic capacitor.
 47. An apparatus for adjusting photo-sensor image resolution comprising: means for providing an array of image photo-sensors, wherein said array of image photo-sensors is organized in columns and rows and has a plurality of sensor types arranged in a pattern to detect light and convert said light to a light conversion electrical signal, whereby each sensor type detects unique colors of said light; means for communicating with said array of image photo-sensors to partition said array of image photo-sensors into a plurality of sub-groups of said array of image photo-sensors and provide partition control signals; means for column averaging said light conversion electrical signals from photo-sensors detecting common colors from the columns of each of said plurality of said sub-groups of said array of image photo-sensors from said partition control signals to create column averaged electrical signals of said columns of said plurality of said sub-group of said array of image photo-sensors; and means for row averaging said column averaged electrical signals of each sub-group of photo-sensors that detect said common colors arranged on said columns within each sub-group of the array of image photo-sensors from said partition control signals
 48. The apparatus for adjusting photo-sensor image resolution of claim 47 further comprising: means for providing addressing, timing, control, and select signals to coordinate generation of the light conversion electrical signals from the plurality of sub-groups of the array of image photo-sensors, averaging of the light conversion electrical signals from selected sensors within said sub-group to generate the column averaged electrical signals and provide select signals to activate the step of selectively averaging of the column averaged electrical signals selectively generate the row averaged electrical signals.
 49. The apparatus for photo-sensor image resolution adjustment of claim 47 further comprising: means for sampling and holding the light conversion electrical signals from selected photo-sensors for averaging; and means for providing timing, control, and select signals for sampling and holding said light conversion electrical signals.
 50. The apparatus for photo-sensor image resolution adjustment of claim 48 wherein said means for row averaging comprises a row averaging circuit including: a plurality of row averaging switches, each row averaging switch connected to the column averaging circuit to receive column averaged electrical signals for sensors with said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors to average the column averaged light conversion electrical signals to create the row averaged electrical signals, each of said plurality of row averaging switches to receive said addressing, timing, control, and select signals to selectively connect said column averaging circuits of sensors having said common colors on the rows of each of said plurality of sub-groups of said array of image photo-sensors for said averaging.
 51. The apparatus for photo-sensor image resolution adjustment of claim 48 wherein means for column averaging comprises a column averaging circuit includes: a first plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having a common color of the array of image photo-sensors on the columns; and a first plurality of averaging switches connected to receive the electrical signal from an adjacent photo-sensor on said columns to selectively transfer said electrical signal from said adjacent photo-sensor to a first selected averaging capacitor to average the conversion electrical signals from an attached photo-sensor and the adjacent photo-sensors, each of said first plurality of averaging receive said timing, control, and select signals to electively connect one said averaging capacitors to average the light conversion electrical signals of said associated photo-sensors of the array of image photo-sensors on the columns.
 52. The apparatus for photo-sensor image resolution adjustment of claim 51 wherein the column averaging circuit further comprises: a second plurality of averaging capacitors, each averaging capacitor connected to receive the light conversion electrical signal from the photo-sensors of a photo-sensor having the common color of the array of image photo-sensors on the columns; and a second plurality of averaging switches connected to receive the light conversion electrical signals from the adjacent photo-sensor on said rows to selectively transfer said electrical signal from said adjacent photo-sensor to a selected second averaging capacitor to average the electrical signals from an attached sensor and the adjacent photo-sensors, each of said second plurality of averaging switches receive said timing, control, and select signals to selectively connect said second averaging capacitors to average the light conversion electrical signals of said associated sensors of the array of image photo-sensors on the rows.
 53. The apparatus for photo-sensor image resolution adjustment of claim 47 wherein said photo-sensors are active pixels sensors and said light is impinging upon said array of active pixel sensors to convert the light to the light conversion electrical signal.
 54. The apparatus for photo-sensor image resolution adjustment of claim 47 further comprising means for selectively amplifying and conditioning one of a group of electrical signals consisting of the light conversion electrical signals and the row averaging electrical signals for external processing.
 55. The apparatus for photo-sensor image resolution adjustment of claim 47 further comprising: means for isolating said light conversion electrical signals, said column averaged electrical signals, and said row averaged electrical signals from effects of a parasitic capacitor. 